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Table of Contents

Release Notes for Cisco Cache Software, Release 2.3.0

Release Notes for Cisco Cache Software, Release 2.3.0

November 3, 2000


Note   The most current Cisco documentation for released products is available on Cisco Connection Online (CCO) at http://www.cisco.com. The online documents may contain updates and modifications made after the hardcopy documents were printed.

Contents

These release notes describe the following topics:

Introduction

These release notes describe new commands included in Cisco Cache Software, Release 2.3.0 for the Cisco Content Engines and Cisco Cache Engines. To simplify terminology, both the Cache Engine and the Content Engine are referred to as the "CE." Refer to the Cisco Cache Software Configuration Guide for the following information:

Refer to the Cisco Cache Software Command Reference, Release 2.3.0 for global configuration, EXEC, show, and interface command descriptions. See the Cisco Content Engine 500 Series Hardware Installation Guide for information on the Cisco Content Engines.


Note   WCCP is variously known as the Web Cache Control Protocol, and the Web Cache Coordination Protocol.

Determining the Operating Software Version


Note   We recommend that you install the most recent software release available for your model of the CE.

To determine the version of the software currently running on the Cisco CE, log on to the CE and enter the show version EXEC command.

Downloading Cache Software

CE Cache software can be downloaded from the Cisco Systems Software Center at the following URL:

http://www.cisco.com/cgi-bin/tablebuild.pl/cache-engine

Upgrading to a New Software Release

As of the date of this release note, two types of CE Cache software files are available on CCO to download: files with the .pax suffix and files with the .bin suffix. The .pax file contains the full-image software with the graphical user interface (GUI) and is the file routinely installed. The .bin file software is for recovery situations that require booting from the network, or restoring Flash memory. Refer to the section "Recovering the System Software" in the Cisco Cache Software Configuration Guide for instructions on loading your system image with the .bin file.


Step 1   Use an FTP client to transfer the .pax file to the /local directory of your CE.

Step 2   Log on to the CE, and at the priveleged level EXEC command prompt enter:

install filename.pax

where filename is the name of the .pax file.

Step 3   Follow the command-line interface instructions as prompted. At the following prompt, enter y:

Copy new image to flash memory?[yes]:

Step 4   After the CE has rebooted, use the show version command to display the current
software version.


New and Changed Information

New Hardware Features in Cache Software Release 2.3.0

Release 2.3.0 of the Cisco Cache software adds support for the Content Engine 507, 560 and 590.

New Software Features in Cache Software Release 2.3.0

Release 2.3.0 operates all models of the Cisco 500 Series Cache Engines as well as the Cisco Content Engine 590, 507, and 560. To simplify terminology, both the Cache Engine and the Content Engine are referred to as the "CE" in this document.

FTP Caching

The CE can fulfill File Transfer Protocol (FTP) requests, and cache FTP content for web clients that are configured to use the CE as a proxy server. The ftp global configuration command was added to the command line interface (CLI).

ftp Command

Use the ftp global configuration command to configure FTP caching services on the CE. Use the no form of the command to selectively disable options.

ftp {age-multiplier directory-listing dl_time file fo_time | max-ttl {days directory-listing dlmax_days file fmax_days | hours directory-listing dlmax_hours file fmax_hours | minutes directory-listing dlmax_ min file fmax_min | seconds directory-listing dlmax_ sec file fmax_sec} | min-ttl min_minutes | object max-size size | proxy {anonymous-pswd passwd | incoming port | outgoing host {hostname | ipaddress} port} | reval-each-request {all | directory-listing | none} | serve-ims directory-listing age_percent file age_percent}

no ftp {age-multiplier directory-listing dl_time file fo_time | max-ttl {days directory-listing dlmax_days file fmax_days | hours directory-listing dlmax_hours file fmax_hours | minutes directory-listing dlmax_ min file fmax_min | seconds directory-listing dlmax_ sec file fmax_sec} | min-ttl min_minutes | object max-size size | proxy {anonymous-pswd passwd | incoming port | outgoing host {hostname | ipaddress} port} | reval-each-request {all | directory-listing | none} | serve-ims directory-listing age_percent file age_percent}

Syntax Description

age-multiplier

FTP caching heuristic modifiers.

directory-listing

Heuristic modifier for directory listing objects.

dl_time

Expiration time of directory listing objects as a percentage of their age (0-100). The default is 30.

file

Heuristic modifier for file objects.

fo_time

Expiration time of file objects as a percentage of their age (0-100).
The default is 60.

max-ttl

Sets maximum Time To Live for objects in the cache.

days

Sets maximum Time To Live units in days.

directory-listing

Sets maximum Time To Live for directory listing objects in days.

dlmax_days

Specifies maximum Time To Live in days for directory listing objects (1-1825). The default is 7 days.

file

Sets maximum Time To Live for file objects in days.

fmax_days

Specifies the maximum Time To Live in days (1-1825). The default is 3 days.

hours

Sets maximum Time To Live units in hours.

directory-listing

Sets maximum Time To Live for directory listing objects in hours.

dlmax_hours

Specifies maximum Time To Live for directory listing objects in hours (1-43800). The default is 72 hours.

file

Sets maximum Time To Live for file objects in hours.

fmax_hours

Specifies the maximum Time To Live for file objects in hours (1-43800).
The default is 168 hours.

minutes

Sets maximum Time To Live units in minutes.

directory-listing

Sets maximum Time To Live for directory listing objects in minutes.

dlmax_ min

Specifies the maximum Time To Live for directory listing objects in minutes (1-2628000). The default is 4320 minutes.

file

Sets maximum Time To Live for file objects in minutes.

fmax_min

Specifies the maximum Time To Live for file objects in minutes (1-2628000). The default is 10080 minutes.

seconds

Sets maximum Time To Live units in seconds.

directory-listing

Sets maximum Time To Live for directory listing objects in seconds.

dlmax_ sec

Specifies the maximum Time To Live for directory listing objects in seconds (1-157680000). The default is 259200 seconds.

file

Sets maximum Time To Live for file objects in seconds.

fmax_sec

Specifies the maximum Time To Live for file objects in seconds (1-157680000). The default is 604800 seconds.

min-ttl

Sets minimum Time To Live for FTP objects in cache.

min_minutes

Specifies the minimum Time To Live in minutes for FTP objects in cache (0-86400).

object

Sets configuration of FTP objects.

max-size

Sets maximum size of a cachable object.

size

Specifies the maximum size of a cachable object in KB (1-1048576).

proxy

Sets proxy configuration parameters.

anonymous-pswd

Sets anonymous password string (for example, wwwuser@cisco.com).

passwd

Specifies the anonymous password. The default is anonymous@hostname.

incoming

Sets the incoming port for proxy-mode requests.

port

Specifies up to eight ports to listen for requests (1-65535).

outgoing

Sets parameters to direct outgoing FTP requests to another proxy server.

host

Sets outgoing FTP proxy host parameters.

hostname

Specifies the hostname of the outgoing FTP proxy.

ipaddress

Specifies the IP address of the outgoing FTP proxy.

port

Specifies the port of the outgoing FTP proxy (1-65535).

reval-each-request

Sets scope of revalidation for every request.

all

Revalidates all objects on every request.

directory-listing

Revalidates directory listing objects on every request.

none

Does not revalidate for each request.

serve-ims

Sets the handling of "if-modified-since" requests.

directory-listing

Modifies handling of "if-modified-since" requests for directory listing objects.

age_percent

Specifies the percentage of age to serve the object without revalidation (0-100). The default is 50.

file

Modifies handling of if-modified-since requests for file objects.

age_percent

Specifies percentage of age to serve the object without revalidation (0-100). The default is 80.

Defaults

Command Modes

Global configuration

Usage Guidelines

The CE can fulfill ftp:// style FTP requests over HTTP transport in proxy mode.

When the CE receives an FTP request from the Web client, it first looks in its cache. If the object is not in its cache, it fetches the object from an upstream FTP proxy server (if one is configured), or directly from the origin FTP server.

The CE caches both the FTP file objects and directory listings. The content (directory listings and files) is stored in CFS.

The FTP proxy supports passive and active mode for fetching files and directories. Passive mode is the default. The CE automatically changes to active mode if passive mode is not supported by the FTP server.

The FTP proxy supports anonymous as well as authenticated FTP requests. Only base64 encoding is supported for authentication. The FTP proxy accepts all FTP URL schemes defined in RFC 1738. In the case of a URL in the form ftp://user@site/dir/file, the proxy sends back an authentication failure reply and the browser supplies a popup window for the user to enter login information.

The FTP proxy supports commonly used MIME types, attaches the corresponding header to the client, chooses the appropriate transfer type (binary or ASCII), and enables the browser to open the FTP file with the configured application. For unknown file types, the proxy uses binary transfer as default and instructs the browser to save the download file instead of opening it. The FTP proxy returns a formatted directory listing to the client if the FTP server replies with a known format directory listing. The formatted directory listing has full information about the file or directory and provides the ability for users to choose the download transfer type.

The CE caches FTP traffic only when the client uses the CE as a proxy server for FTP requests. All FTP traffic that was sent directly from the Web client to an FTP server, if transparently intercepted by the CE, is treated as non-HTTP traffic.

The FTP proxy supports up to eight incoming ports. It can share the ports with transparent-mode services and also with the other proxy-mode protocols supported by the CE, such as HTTP and HTTPS. In proxy-mode, the CE accepts and services the FTP requests only on the ports configured for FTP proxy. All the FTP requests on other proxy-mode ports are rejected in accordance with the error-handling settings on the CE.

The CE can apply the rules template to FTP requests based on server name, domain name, server IP address and port, client IP address, and URL.

The CE logs FTP transactions in the transaction log, in accordance with the Squid syntax. When URL tracking is enabled, the CE logs FTP transaction information to the syslog. The syslog entries are prefixed with <ftp>.

Examples

This example configures an incoming FTP proxy on ports 8080, 8081, and 9090. Up to eight incoming proxy ports can be configured on the same command line.

CE(config)# ftp proxy incoming 8080 8081 9090

This example removes one FTP proxy port from the list entered in the previous example. Ports 8080 and 9090 remain FTP proxy ports.

CE(config)# no ftp proxy incoming 8081

This example disables all the FTP proxy ports.

CE(config)# no ftp proxy incoming

This example configures an upstream FTP proxy with the IP address 172.76.76.76 on port 8888.

CE(config)# ftp proxy outgoing host 172.76.76.76 8888

This example specifies an anonymous password string for the CE to use when contacting FTP servers. The default password string is anonymous@hostname.

CE(config)# ftp proxy anonymous-pswd newstring@hostname

This example configures the maximum size in kilobytes of an FTP object that the CE will cache. By default, the maximum size of a cachable object is not limited.

CE(config)# ftp object max-size 15000

This example forces the CE to revalidate all objects for every FTP request.

CE(config)# ftp reval-each-request all

This example configures a maximum Time To Live of 3 days in cache for directory listing objects and file objects.

CE(config)# ftp max-ttl days directory-listing 3 file 3

Related Commands

rule use-proxy

show ftp

show statitics ftp

show ftp Command

To display the configuration of the File Transfer Protocol (FTP) on the CE, use the show ftp command.

show ftp

Syntax Description

The show ftp command has no keywords or options.

Defaults

No default behavior or values

Command Modes

EXEC

Examples

Console# show ftp FTP heuristic age-multipliers: directory-listing 30% file 60% Maximum time to live in days : directory-listing 3 file 7 Minimum time to live in minutes: 60 No objects are revalidated on every request. Serve-IMS without revalidation if... Directory listing object is less than 50% of max age File object is less than 80% of max age Incoming Proxy-Mode: Servicing Proxy mode FTP connections on ports: 22 23 88 66 48 488 449 90 Outgoing Proxy-Mode: Not using outgoing proxy mode. Maximum size of a cachable object is unlimited. Console#

Related Commands

ftp

show statistics ftp

show statistics ftp Command

To display FTP related statistic, use the show statistics ftp option.

show statistics ftp

Syntax Description

The show statistics ftp command has no keywords or options.

Defaults

No default behavior or values

Command Modes

EXEC

Examples

CE# show statistics ftp FTP Statistics -------------- FTP requests Received = 9 FTP Hits Requests Percentage Number of hits = 2 22.2 % Bytes = 13542 22.0 % FTP Misses Requests Percentage Number of misses = 7 77.8 % Bytes = 47946 78.0 % Requests sent to Outgoing Proxy = 7 Requests sent to origin ftp server = 0 FTP error count = 0

To clear the FTP caching statistics statistics:

CE# clear statistics ftp

Related Commands

ftp

show ftp

FTP Proxy Page

The FTP Proxy page has been added to the Caching menu, as shown in Figure 1. See the FTP Proxy online help for further information.


Figure 1: Management GUI— FTP Proxy Page


FTP Freshness Page

The FTP Freshness page has been added to the Caching menu, as shown in Figure 3. See the FTP Freshness online help for further information.


Figure 2: Management GUI— FTP Freshness Page


Proxy Failover

The proxy failover feature reduces the incidence of server failure errors returned to the client. An administrator can configure a logical failover chain of outgoing HTTP proxy servers. One of the servers is designated as primary and receives the outgoing proxy traffic. If the primary server fails, the next server in the logical chain of proxy servers assumes the load. If that server fails, the next one takes over and so on. Use the http proxy outgoing global configuration command to configure up to eight failover outgoing proxies. The complete http syntax and usage guidelines are included to provide context.

http Command

To configure HTTP-related parameters, use the http global configuration command. To disable HTTP related-parameters, use the no form of this command.

http {age-multiplier {text texttime binary bintime} | append {ldap-proxy-auth-header {hostname | ipaddress}| via-header | x-forwarded-for-header} | authenticate-strip-ntlm | cache-authenticated | cache-cookies | cache-miss revalidate | cache-on-abort {enable | max maxthresh | min minthresh | percent percenthresh} | cluster max-delay delayseconds misses totalmisses | l4-switch enable | max-ttl {days text textdays binary bindays | hours text texthours binary binhours | minutes text textminutes binary binminutes | seconds text textseconds binary binseconds} | min-ttl minutes | object {max-size maxsize | url-validation enable} | persistent-connections {enable | max-idle connections | timeout secs [max-idle connections]} | proxy {incoming port | outgoing {host {hostname | ipaddress} port [primary]} | monitor seconds | origin-server} | reval-each-request {all | none | text} | serve-ims text textpercentage binary binpercentage}

no http {age-multiplier {text texttime binary bintime} | append {ldap-proxy-auth-header {hostname | ipaddress}| via-header | x-forwarded-for-header} | authenticate-strip-ntlm | cache-authenticated | cache-cookies | cache-miss revalidate | cache-on-abort {enable | max maxthresh | min minthresh | percent percenthresh} | cluster max-delay delayseconds misses totalmisses | l4-switch enable | max-ttl {days text textdays binary bindays | hours text texthours binary binhours | minutes text textminutes binary binminutes | seconds text textseconds binary binseconds} | min-ttl minutes | object {max-size maxsize | url-validation enable} | persistent-connections {enable | max-idle connections | timeout secs [max-idle connections]} | proxy {incoming port | outgoing {host {hostname | ipaddress} port [primary]} | monitor seconds | origin-server} | reval-each-request {all | none | text} | serve-ims text textpercentage binary binpercentage}

Syntax Description

age-multiplier

HTTP/1.0 caching heuristic modifiers.

text

Heuristic modifier for text object.

texttime

Expiration time of text objects as a percentage of their age (0-100).

binary

Heuristic modifier for binary object.

bintime

Expiration time of binary objects as a percentage of their age (0-100).

append

Configures HTTP headers to be included by CE.

ldap-proxy-auth-header

Forwards "Proxy Authorization" headers in outbound requests.

hostname

Host name of upstream proxy or server that will perform LDAP authentication.

ipaddress

IP address of upstream proxy or server that will perform LDAP authentication.

via-header

Includes "Via" header in responses and replies.

x-forwarded-for-header

Notifies Web server of client's IP address through "X-Forwarded-For" header.

authenticate-strip-ntlm

Strips NT LAN Manager (NTLM) authentication headers.

cache-authenticated

Caches and revalidates authenticated Web objects.

cache-cookies

Caches Web objects with associated cookies.

cache-miss

Configuration for the handling of "no-cache" requests.

retrieve

Retrieves the object from the point of origin.

revalidate

Revalidates the object with the origin before serving.

cache-on-abort

Sets cache-on-abort configuration options.

enable

Enables cache-on-abort feature.

max

Sets maximum threshold.

maxthresh

Value in kilobytes of maximum threshold (1-99999). Default is 256.

min

Sets minimum threshold.

minthresh

Value in kilobytes of minimum threshold (1-99999). Default is 32.

percent

Sets percent threshold.

percenthresh

Percentage value (1-99). Default is 80 percent.

cluster

Sets cache cluster configuration options.

max-delay

Maximum delay to wait for a response.

delayseconds

Maximum delay in seconds (0-10).

misses

Duration of healing mode (misses).

totalmisses

Total number of misses before healing is disabled (0-999).

l4-switch enable

Enables Layer 4 switch redirection.

max-ttl

Maximum Time To Live for objects in the cache.

days

Sets maximum Time To Live for units in days.

hours

Sets maximum Time To Live for units in hours.

minutes

Sets maximum Time To Live for units in minutes.

seconds

Sets maximum Time To Live for units in seconds.

text

Sets maximum Time To Live for text objects.

binary

Sets maximum Time To Live for binary objects.

days

Specifies maximum Time To Live for units in hours.

hours

Specifies maximum Time To Live for units in hours.

minutes

Specifies maximum Time To Live for units in minutes.

seconds

Specifies maximum Time To Live for units in seconds.

min-ttl

Sets minimum time for objects to live.

minutes

Specifies minimum time to live in minutes (0-86400).

object

Sets URL validation and maximum size of HTTP objects.

max-size

Sets the maximum size of a cachable object.

maxsize

Maximum size of a cachable object in kilobytes (1-1048576).

url-validation enable

Enables each HTTP validation request.

persistent-connections

Persistent connections configuration options.

enable

Enables persistent connections.

max-idle

Sets maximum number of idle persistent connections.

connections

Maximum number of idle persistent connections (1-4096).

timeout secs

Persistent connections timeout in seconds (1-86400).

proxy

Configuration parameters for proxy mode.

incoming

Configuration for incoming proxy-mode requests.

port

Port on which to listen for incoming HTTP proxy requests (1-65535). Default is port 8080.

outgoing

Configuration to direct outgoing request to another proxy server.

host

Use outgoing HTTP proxy.

hostname

Hostname of outgoing proxy.

ipaddress

IP address of outgoing proxy.

port

Port number of outgoing proxy (1-65535).

primary

(Optional.) Makes the proxy being configured the primary proxy server.

monitor

Interval at which to monitor the outgoing proxy servers.

seconds

Monitoring interval in seconds (10-300).

origin-server

Use origin server if all proxies are failed.

reval-each-request

Configuration of revalidation for every request.

all

Revalidates all objects on every request.

none

Does not revalidate for each request.

text

Revalidates text objects on every request.

serve-ims

Configuration for the handling of if-modified-since (IMS) requests for text objects.

text

Modifies handling of if-modified-since requests for text objects.

textpercentage

Percentage of age to serve the text object without revalidation (0-100).

binary

Modifies handling of if-modified-since requests for binary objects.

binpercentage

Percentage of age to serve the binary object without revalidation (0-100).

Defaults

See the corresponding syntax description for default values.

Command Modes

Global configuration

Usage Guidelines

HTTP Proxy Failover Option

The http proxy outgoing option configures backup proxy servers for HTTP proxy failover support. One proxy server functions as the primary proxy server and all requests are redirected to it. If the primary proxy server fails to respond to the HTTP CONNECT, the server is noted as failed and the requests are redirected to the next outgoing proxy server until one of the proxies service the request.

To explicitly designate the primary proxy, use the primary keyword. If several proxies are configured with the primary keyword, the last one configured overrides the others. Failover to a proxy server occurs in the order the proxy servers were configured. In the event that all the configured proxy servers fail, the CE can optionally redirect requests to the origin server if the user enters the http proxy outgoing origin-server option. If the user has configured the origin-server option, the CE directs HTTP requests to the original server specified in the HTTP header. If the option is not enabled, the client receives the error. Response errors and read errors are returned to the client, since it is not possible to detect whether these errors are generated at the origin server or at the proxy. Up to eight outgoing proxy servers can be configured for a single CE.

The state of the proxy servers is maintained by active monitoring, which occurs in the background. The state of the proxy servers can be seen in the CLI and syslog NOTICE messages. This interval is configured with the http proxy outgoing monitor option. This outgoing monitor interval is the frequency with which a single proxy server is polled. Only one proxy server is polled per interval. If more than one proxy server is configured, the delay is in multiple intervals of the monitor value. If one of the proxy servers is unavailable, the polling mechanism waits for the connect timeout before polling the next server.

The configuration specified by the rule command has precedence over any other configured proxy server. If an administrator created a use-proxy rule, the HTTP request is directed only to the proxy specified by the rule. For example:

Requests to the domain "cisco.com" failover to the backup proxies if ipaddr1 is unavailable. Any other rule that uses ipaddr1 fails over to the backup proxies when ipaddr1 fails. Each request is checked to determine if the protocol supports failover (currently, only HTTP). If so, those requests failover to the list of outgoing proxies configured with the http proxy outgoing host option. In the event that all proxy servers fail, the failover of the rule command sends the request to the origin server if the http proxy outgoing origin-server option is entered.

Requests with destinations included in the proxy-protocols outgoing-proxy exclude list bypass the CE proxy as well as the failover proxies.

When an HTTP request intended for another proxy server is intercepted by the CE in transparent mode, the CE forwards the request to the intended proxy server if the proxy-protocols transparent original-proxy command was entered.

The proxy failover feature currently supports only HTTP, and not HTTPS or FTP.

Other HTTP Configuration Options

Note   Text objects refer to HTML pages. Binary objects refer to all other Web objects (for example, GIFs or JPEGs).

If a cached object's HTTP header does not specify an expiration time, the age-multiplier and max-ttl options provide a means for the CE to age cached objects. The CE's algorithm to calculate an object's cache expiration date is as follows:

Expiration date = (Today's date - Object's last modified date) * Freshness factor

The freshness factor is computed from the text and binary percentage parameters of the age-multiplier command. Valid age-multiplier values are 0 to 100 percent of the object's age. Default values are 30 percent for text and 60 percent for binary objects. After the expiration date, the object is considered stale and subsequent requests result in a fresh retrieval by the CE.

The max-ttl option sets the upper limit on estimated expiration dates. An explicit expiration date in the HTTP header takes precedence over the configurable TTL (Time To Live).

The serve-ims option responds to an if-modified-since request issued from a client browser by serving the object directly from the cache without revalidating with the origin server whether the object is less than the configured percentage of its maximum age.

The cache-cookies option enables the CE to cache binary served with HTTP set-cookies headers and no explicit expiration information.

The cache-authenticated option enables the CE to cache authenticated content. If this command is enabled, the CE will not serve authenticated objects without first revalidating the authentication header attached to the cached object.

The reval-each-request option enables the CE to revalidate all objects requested from the cache, text objects only, or none at all.

The cache-miss revalidate option revalidates a cache-miss request forced by the client (shift-reload). The cache-miss retrieve option forces a new object retrieval.

Use the object max-size option to specify the maximum size in kilobytes of a cachable object. The default is no maximum size for a cachable object. The no form of the command resets the default value.

The cluster option modifies the healing mode parameters. A cluster refers to a group of two or more CEs within a single WCCP Version 2 environment. Healing mode describes the addition of a CE to an existing network, and the resulting "healing" time it takes to fill the cache with content. To disable healing mode, you must set the number of misses to 0.

The proxy mode option enables the CE to operate in environments where WCCP is not enabled, or where client browsers have previously been configured to use a legacy proxy server. You must configure the proxy incoming port to accept proxy-style requests using the proxy incoming port option.

To configure the CE to direct all HTTP miss traffic to a parent cache (without using ICP or WCCP), use the proxy outgoing hostname port option, in which hostname is the system name or IP address of the outgoing proxy server, and port is the port number designated by the outgoing (upstream) server to accept proxy requests.

The cache-on-abort option provides user-defined thresholds to determine whether or not the CE will complete the download of an object when the client has aborted the request. When the download of an object aborts before it is completed, the object is not stored on the CE or counted in the hit-rate statistics. Client abort processing occurs when a client of the CE aborts the download of a cachable object before the download is complete. Typically, a client aborts a download by clicking the Stop icon on the browser, or by closing the browser during a download.

If the cache-on-abort option is enabled and all cache-on-abort thresholds are disabled, then the CE always aborts downloading an object to the cache. If the CE determines that there is another client currently requesting the same object, downloading is not aborted. The CE only applies those thresholds that have been enabled.

The l4-switch enable option enables the CE to transparently receive redirected HTTP traffic from Layer 4 switches with transparency features. See the switch documentation for specific configuration information.

Configure the http ldap-proxy-auth-header global configuration option when the CE and an upstream server or proxy is performing LDAP authentication.

To prevent disclosure of a user's proxy authentication credentials to another host, the CE removes the HTTP Proxy-Authorization header from the HTTP request when it forwards the request. With LDAP authentication it is important that upstream proxies share the authentication credentials carried in the header. To prevent the CE from stripping out the HTTP Proxy-Authorization header, enter the
http append ldap-proxy-auth-header global configuration command. The CE will forward the Proxy-Authorization header with credentials to the specified host name or IP address.

The persistent-connections enable command enables persistent connections on the CE. To configure the number of seconds the CE should wait for a connection response before it times out, use the timeout option. To set the number of seconds that the CE should allow an idle persistent connection to remain open, use the max-idle option.

The http object url-validation option has a dependency with the ip name-server CLI command. When the ip name-server option is not configured (for example, during transparent proxy), http object url-validation is dynamically turned off. When the ip name-server option is configured, http object url-validation is turned on automatically if and only if it was enabled.


Caution   URL validation is on by default. Cisco Systems strongly recommends that you keep URL validation enabled, because disabling URL validation might make the CE vulnerable to corruption from the HTTP objects in the cache.

Use the exclude list option in the http proxy outgoing global configuration command to specify domains for which the CE will not use an upstream proxy.

Only one domain can be specified per command line. To specify multiple domains for proxy exclusion, iteratively execute the command for each domain. In the following example, cisco.com and the address 10.9.8.7 are proxy-excluded.

Console(config)# http proxy outgoing exclude list cisco.com Console(config)# http proxy outgoing exclude list 10.9.8.7

The maximum number of no-proxy domains is 64. The CE will not use an upstream proxy for any domain that ends with a listed domain name. For example, if you specify cisco.com, the configured outgoing proxy server will be bypassed each time the CE tries to retrieve a Web page from videos.cisco.com, or personals.cisco.com.

For IP addresses, enter the full IP address or use the asterisk "*" as a wildcard for IP address fields as follows:

172.16.1.*

172.16.*.*

172.*.*.*

The syntax 172.16.*.* indicates that all requests to the domain host of 172.16.xxx.xxx will be excluded. Wildcard syntax does not support "0" or "?".

The following forms of wildcard specification are not supported:

172.*.10.2

172.31.1*.8

Examples

In this example, the host 10.1.1.1 on port 8088 is designated the primary proxy server, and host 10.1.1.2 is a backup proxy server.

CE(config)# http proxy outgoing host 10.1.1.1 8088 primary CE(config)# http proxy outgoing host 10.1.1.2 220

In this example, the CE is configured to redirect requests directly to the origin server in the event that all of the proxy servers fail.

CE(config)# http proxy outgoing origin-server

In this example, the CE is configured to monitor the proxy servers every 120 seconds.

CE(config)# http proxy outgoing monitor 120

To disable any of the above, use the no version of the command.

Proxy Failover Show Commands
Console# show http proxy Incoming Proxy-Mode: Servicing Proxy mode HTTP connections on ports: 8080 Outgoing Proxy-Mode: Primary proxy server: 172.69.63.150 port 1 Failed Backup proxy servers: 172.69.236.151 port 8005 172.69.236.152 port 123 172.69.236.153 port 65535 Failed 172.69.236.154 port 10 Proxy monitor interval: 60 seconds Use Origin Server upon Proxy Failure.
Statistics
Console# show statistics http requests Statistics - Requests Total % of Requests --------------------------------------------------- Total Received Requests: 43 - Forced Reloads: 0 0.0 Near Hits: 0 0.0 Server Errors: 0 0.0 URL Blocked: 0 0.0 Sent to Outgoing Proxy: 32 74.4 Failures from Outgoing Proxy: 0 0.0 Excluded from Outgoing Proxy: 11 25.6 ICP Client Hits: 0 0.0 ICP Server Hits: 0 0.0 HTTP 0.9 Requests: 0 0.0 HTTP 1.0 Requests: 43 100.0 HTTP 1.1 Requests: 0 0.0 HTTP Unknown Requests: 0 0.0 Non HTTP Requests: 0 0.0 Non HTTP Responses: 0 0.0 Chunked HTTP Responses: 0 0.0 Flow-controlled HTTP streams: 2 4.7 Http Miss Due To DNS: 0 0.0 Http Deletes Due to DNS: 0 0.0 Objects cached for min ttl: 0 0.0 Console# show statistics http proxy out HTTP Outgoing Proxy Statistics Attempts Failures Successes Cleared ---------------------------------------------------- 10.1.1.1: 0 1 0 0 172.31.227.111: 32 0 0 40 Requests when all proxies were failed: 0 Console(config)# http append ldap-proxy-auth-header ? Hostname or A.B.C.D IP address or hostname of proxy/server to receive proxy-auth headers Console(config)# http append ldap-proxy-auth-header 172.16.1.1 Console(config)# http age-multiplier text 30 bin 60 Console(config)# http reval-each-request text Console(config)# no http age-multiplier text 30 bin 60 Console(config)# no http reval-each-request text
    Console(config)# http cache-on-abort enable
    Console(config)# no http cache-on-abort
    Console(config)# http cache-on-abort min 16
    Console(config)# no http cache-on-abort min
The cache-on-abort max and percent thresholds are configured like the minimum threshold shown in the examples.

Related Commands

ldap

proxy-protocols

rule no-proxy

rule use-proxy

show http

show http proxy

show ldap

show statistics http requests

show statistics http proxy outgoing

HTTP Proxy Page

The proxy failover feature is configured on the HTTP Proxy page in the Caching menu, as shown in Figure 3. See the HTTP Proxy online help for further information.


Figure 3: Management GUI—HTTP Proxy Page


TACACS+ Support

The Terminal Access Controller Access Control System (TACACS) validates users before they gain access to the router. TACACS is derived from the United States Department of Defense (RFC 1492) and is used by Cisco Systems as an additional control of non-privileged and privileged mode router access. Software Release 2.3.0 supports TACACS+ only and not TACACS or Extended TACACS. To configure TACACS+, use the authentication and tacacs commands.

authentication Command

To configure Terminal Access Controller Access Control System Plus (TACACS+), authentication and authorization options, use the authentication global configuration command. Use the no form of the command to selectively disable options.

authentication {configuration {local enable | tacacs enable [primary]} | login {local enable | tacacs enable [primary]}}

no authentication {configuration {local enable | tacacs enable [primary]} | login {local enable | tacacs enable [primary]}}

Syntax Description

configuration

Sets authorization mode.

local enable

Enables local database for authorization.

tacacs enable

Enables TACACS+ database for authorization.

primary

(Optional.) Sets TACACS+ server authorization as a primary.

login

Sets authentication mode.

local enable

Enables local database for authentication.

tacacs enable

Enables TACACS+ database for authentication.

primary

(Optional.) Sets TACACS+ server authentication as a primary.

Defaults

Local authentication is enabled and TACACS+ authentication is disabled.

Command Modes

Global configuration

Usage Guidelines

Authentication or login is the action of identifying and validating a user. It verifies a username with the password. Authorization or configuration is the action of determining what a user is allowed to do.

Login and configuration privileges can be maintained in two databases: the local database, which resides on the CE, and the TACACS+ remote database, which resides on a remote server. The user global configuration commands or the Users GUI page provides a way to add, delete, or modify users' names, passwords, and access privileges in the local database. The TACACS+ remote database can also be used to maintain login and configuration privileges for CE administrative users. The tacacs command or the TACACS+ GUI page allows you to configure the network parameters required to access the remote database.

Login and configuration privileges can be obtained from both the local database or the TACACS+ remote database. If both databases are enabled, then both databases are queried; if the user data cannot be found in the first database queried, then the second database is tried. When the primary keyword is entered for TACACS+ login or configuration authentication (authentication login tacacs enable primary, authentication configuration tacacs enable primary), the TACACS+ database is queried first, and the local database is queried second. If TACACS+ is not designated as primary, and both local and TACACS+ are enabled, the local database is queried first. If both local and TACACS+ are disabled (no authentication), the CE verifies that both are disabled and if so, sets the CE to the default state.

By default, local authentication is enabled and TACACS+ authentication is disabled. When the TACACS+ authentication is disabled, the local authentication is automatically enabled.

Examples

This example disables local configuration authentication.

CE(config)# no authentication configuration local Local configuration authentication disabled.
Note   If local authentication is disabled and TACACS+ is not configured properly, future logins may fail.

TACACS+ Statistics
CE# show statistics authentication Authentication Statistics -------------------------------------- Number of Local Authentication: 0 Number of TACACS+ Authentication: 4 Total number of Authentication: 4 Number of Local Authorization: 0 Number of TACACS+ Authorization: 4 Total number of Authorization: 4 CE# show statistics tacacs TACACS+ Statistics ----------------- Number of access requests: 8 Number of access deny responses: 7 Number of access allow responses: 1

Related Commands

show authentication

show statistics authentication

show statistics tacacs

show tacacs

tacacs

show authentication Command

To display the current TACACS+ current authentication and authorization configuration, use the show authentication command.

show authentication

Syntax Description

This command has no arguments or keywords.

Defaults

No default behavior or values

Command Modes

EXEC

Examples

Console# show authentication Login Authentication: Console/Telnet Session ----------------------------- ----------------------- local enabled tacacs enabled (primary) Configuration Authentication: Console/Telnet Session ----------------------------- ----------------------- local enabled tacacs enabled

tacacs Command

To configure TACACS+ server-related parameters, use the tacacs global configuration command.

tacacs {key keyword | retransmit retries | server {hostname | ipaddress} [primary] | timeout seconds}

Syntax Description

key

Sets security word.

keyword

Specifies keyword. An empty string is the default.

retransmit

Sets number of times requests are retransmitted to a server.

retries

Specifies number of attempts allowed (1-10). The default is two retry attempts.

server

Sets a server address.

hostname

Specifies host name of TACACS+ server.

ipaddress

Specifies IP address of TACACS+ server.

primary

Sets server as primary.

timeout

Sets number of seconds to wait before a request to a server is timed out.

seconds

Specifies the timeout in seconds (1-255). The default is 5 seconds.

Defaults

An empty keyword string is the default. The default timeout time is 5 seconds. The default number of retry attempts is two.

Command Modes

Global configuration

Usage Guidelines

A TACACS+ server must be configured before you enable TACACS+ authentication on the CE. The CE can be configured to use the local password authentication if the TACACS+ password authentication fails. See the "authentication Command" section for more information.

Use the tacacs key command to specify the TACACS+ key, used to encrypt the packets transmitted to the server. This key must be the same as the one specified on the server daemon. The maximum number of characters in the key should not exceed 99 printable ASCII characters (except tabs). An empty key string is the default. All leading spaces are ignored; spaces within and at the end of the key string are not ignored. Double quotes are not required even if there are spaces in the key, unless the quotes themselves are part of the key.

One primary and two backup TACACS+ servers can be configured; authentication is attempted on the primary server first, then on the others in the order in which they were configured. The primary server is the first server configured unless another is explicitly specified as primary with the tacacs server hostname primary command.

The tacacs timeout is the number of seconds the CE waits before declaring a timeout on a request to a particular TACACS+ server. The range is from 1-255 seconds with 5 seconds as the default. The number of times the CE repeats a retry-timeout cycle before trying the next TACACS+ server is specified by the tacacs retransmit command. The default is two retry attempts.

Three unsuccessful login attempts are permitted. TACACS+ logins may appear to take more time than local logins depending on the number of TACACS+ servers and the configured timeout and retry values.

Examples

This example configures the key used in encrypting packets.

CE(config)# tacacs key bronzemonkey789

This example configures the host named rasputin as the primary TACACS+ server.

CE(config)# tacacs server rasputin primary

This example sets the timeout interval for the TACACS+ server.

CE(config)# tacacs timeout 10

This example sets the number of times authentication requests are retried (retransmitted) after a timeout.

CE(config)# tacacs retransmit 5

Related Commands

authentication

show authentication

show statistics authentication

show statistics tacacs

show tacacs

show tacacs Command

To display the settings for the Terminal Access Controller Access Control System Plus (TACACS+) server, use the show tacacs EXEC command.

show tacacs

Syntax Description

This command has no arguments or keywords.

Defaults

No default behavior or values

Command Modes

EXEC

Examples

Console# show tacacs Login Authentication for Console/Telnet Session: enabled (primary) Configuration Authentication for Console/Telnet Session: enabled (primary) TACACS Configuration: --------------------- Key = Timeout = 10 seconds Retransmit = 2 times Server Status --------------------- ------ 171.69.236.175 primary 171.69.227.254

You can also display login and configuration authentications using the show authentication command.

CE# show authentication Login Authentication: Console/Telnet Session ----------------------------- ----------------------- local enabled tacacs enabled (primary) Configuration Authentication: Console/Telnet Session ----------------------------- ----------------------- local enabled tacacs enabled (primary)

Related Commands

authentication

show authentication

show statistics tacacs

tacacs

show statistics tacacs Command

To display TACACS+ statistics, use the show statistics tacacs EXEC command.

show statistics tacacs

Syntax Description

This command has no arguments or keywords.

Defaults

No default behavior or values

Command Modes

EXEC

Examples

console# show statistics tacacs TACACS+ Statistics ----------------- Number of access requests: 0 Number of access deny responses: 0 Number of access allow responses: 0

Related Commands

authentication

show authentication

show tacacs

tacacs

TACACS+ Page

The TACACS+ page has been added to the Systems menu. See the TACACS+ online help for further information.


Figure 4: Management GUI—TACACS+ Page


Open Caveats

The following sections describe caveats still open at the printing of these release notes. Caveats describe unexpected behavior in the Cisco Cache software.

Open Caveats—Software Release 2.3.0

Symptom: When the number of active RADIUS authentication requests exceeds 950, requests that have recently been authenticated by the RADIUS server are forced to reauthenticate even though the authentication timeout interval defined by the radius-server authtimeout global configuration command has not expired.

Possible cause: User entries in the RADIUS authentication cache in local CE RAM are not being purged properly. When the authentication cache is full, entries for recently authenticated users cannot be written to the authentication cache, forcing those users to reauthenticate on each attempt to access restricted content.

When the CE authenticates a user through the RADIUS server, a record of that authentication is stored locally in the CE RAM. As long as the authentication entry is kept, subsequent attempts to access restricted content by that user do not require RADIUS server lookups. Entries are purged when they are inactive for a period defined by the authentication timeout interval.

Workaround: There is no workaround, but power cycling the CE clears RAM contents, including the RADIUS authentication cache.

Further information: This caveat will be resolved in Cache software, Release 2.3.1.

Symptom: In some cases, Websense blocking messages for blocked requests are not returned to the client from a Websense server.

Workaround: Ensure that the IP address and host name of the machine running the Websense server are specified in the internal Domain Name System (DNS) servers, or in the websense.ini file. To edit the websense.ini file, complete the following procedure:


Step 1   Go to the Websense directory on the Websense server host.

Step 2   Stop the Websense server.

Step 3   Open the websense.ini file in a text editor.

Step 4   In the [OpenServer] field of the websense.ini file, enter the following command on a blank line:

BlockPageServerName = <IP address>

where <IP address> is the IP address or host name of the computer running the Websense server.

Step 5   Save the edited websense.ini file.

Step 6   Restart the Websense server.


Resolved Caveats

The following section describes caveats from previous releases that are resolved in Release 2.3.0.

Cisco Systems has observed that in topologies with 20 or more routers configured to service multiple Cache Engines, some of the Cache Engines do not receive hash allotments, and thus receive no redirected traffic from the routers. The routers can be configured in either unicast or multicast mode.

Workaround: To correct this condition, reboot each Cache Engine or stop and start the Web Cache Communication Protocol (WCCP) on each Cache Engine using the Cache Engine wccp global configuration command.

For example, to reset WCCP on a Cache Engine in the cache farm configured with basic web caching only, issue the following commands:

    console(config)# no wccp web-cache console(config)# wccp web-cache router-list 1
Wait 30 seconds between stopping and starting WCCP. The wccp keywords and options shown here apply only to the Cache Engine in this example. Use the keywords and options appropriate to the configuration of each Cache Engine.

Display the hash allotments for Cache Engines by using the show ip wccp web-cache detail router command.

The http proxy outgoing exclude list command is currently case sensitive. If a user on Netscape attempts to connect to HOME.INTERNAL.DOMAIN.COM, or Home.Internal.DOMAIN.Com, or any other combination of domain.com that is not all lowercase, then the exclude list domain.com command fails.

In certain cases, Java or JavaScript programs that run on port 80 are reset. The error bypass mechanism (in Cache Engine) fails to insert the correct IP address into the bypass list. Because the bypass list was not correctly updated, the Java or JavaScript traffic on port 80 was never bypassed.

Sometimes the BUCKET_IN flag is not cleared even though the corresponding AWAY flag is cleared in the Cache Engine that previously had the bucket.

When the Cache Engine is in bypass mode, with buckets bypassed, issuing the no load bypass enable command does not disable the bypass mechanism, and thus buckets stay bypassed.

When the origin server sends a large object with the wrong Content Length value, the Cache Engine deletes the object after downloading it. If there are multiple requests for the same object, the remaining clients receive a truncated object after the object is deleted.

When CEs are clustered and WCCP weights are changed dynamically, authenticated HTTP traffic may sometimes not be bypassed, though the authentication bypass feature is enabled
(bypass auth-traffic enable).

Specifying 65535 as an HTTPS destination port causes a page fault error.
(For example, https destination-port allow 65535, and https destination-port deny 65535). This has been fixed in the first post-FCS revision of release 2.2.0

Related Documentation

Cisco Content Engine 500 Series Hardware Installation Guide

Site Preparation and Safety Guide

Cisco Cache Software Configuration Guide

Cisco Cache Software Command Reference, Release 2.3.0

Release Notes for the Cisco Content Engine or Cisco Cache Engine

Regulatory Compliance and Safety Information for the Cisco Content Engine or Cisco Cache Engine

Obtaining Technical Assistance

Cisco provides Cisco Connection Online (CCO) as a starting point for all technical assistance. Warranty or maintenance contract customers can use the Technical Assistance Center. All customers can submit technical feedback on Cisco documentation using the Web, e-mail, a self-addressed stamped response card included in many printed docs, or by sending mail to Cisco.

Cisco Connection Online

Cisco continues to revolutionize how business is done on the Internet. Cisco Connection Online is the foundation of a suite of interactive, networked services that provides immediate, open access to Cisco information and resources at anytime, from anywhere in the world. This highly integrated Internet application is a powerful, easy-to-use tool for doing business with Cisco.

CCO's broad range of features and services helps customers and partners to streamline business processes and improve productivity. Through CCO, you will find information about Cisco and our networking solutions, services, and programs. In addition, you can resolve technical issues with online support services, download and test software packages, and order Cisco learning materials and merchandise. Valuable online skill assessment, training, and certification programs are also available.

Customers and partners can self-register on CCO to obtain additional personalized information and services. Registered users may order products, check on the status of an order and view benefits specific to their relationships with Cisco.

You can access CCO in the following ways:

You can e-mail questions about using CCO to cco-team@cisco.com.

Technical Assistance Center

The Cisco Technical Assistance Center (TAC) is available to warranty or maintenance contract customers who need technical assistance with a Cisco product that is under warranty or covered by a maintenance contract.

To display the TAC web site that includes links to technical support information and software upgrades and for requesting TAC support, use www.cisco.com/techsupport.

To contact by e-mail, use one of the following:

Language E-mail Address

English

tac@cisco.com

Hanzi (Chinese)

chinese-tac@cisco.com

Kanji (Japanese)

japan-tac@cisco.com

Hangul (Korean)

korea-tac@cisco.com

Spanish

tac@cisco.com

Thai

thai-tac@cisco.com

In North America, TAC can be reached at 800 553-2447 or 408 526-7209. For other telephone numbers and TAC e-mail addresses worldwide, consult the following web site: http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml.

Documentation Feedback

If you are reading Cisco product documentation on the World Wide Web, you can submit technical comments electronically. Click Feedback in the toolbar and select Documentation. After you complete the form, click Submit to send it to Cisco.

You can e-mail your comments to bug-doc@cisco.com.

To submit your comments by mail, for your convenience many documents contain a response card behind the front cover. Otherwise, you can mail your comments to the following address:

Cisco Systems, Inc.
Document Resource Connection
170 West Tasman Drive
San Jose, CA 95134-9883

We appreciate and value your comments.

Obtaining Documentation

World Wide Web

You can access the most current Cisco documentation on the World Wide Web at http://www.cisco.com, http://www-china.cisco.com, or http://www-europe.cisco.com.

Documentation CD-ROM

Cisco documentation and additional literature are available in a CD-ROM package, which ships with your product. The Documentation CD-ROM is updated monthly. Therefore, it is probably more current than printed documentation. The CD-ROM package is available as a single unit or as an annual subscription.

Ordering Documentation

Registered CCO users can order the Documentation CD-ROM and other Cisco Product documentation through our online Subscription Services at http://www.cisco.com/cgi-bin/subcat/kaojump.cgi.

Nonregistered CCO users can order documentation through a local account representative by calling Cisco's corporate headquarters (California, USA) at 408 526-4000 or, in North America, call 800 553-NETS (6387).

This document is to be used in conjunction with the documents listed in the "Related Documentation" section.

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