|
|
Use the commands in this chapter to configure and monitor QLLC or SDLLC connections. For QLLC conversion or SDLLC parameter configuration information and examples, refer to the "Configuring IBM Network Protocol Translation" chapter in the Router Products Configuration Guide.
Use the qllc largest-packet interface configuration command to indicate the maximum size of the SNA packet that can be sent or received on an X.25 interface configured for QLLC conversion. Use the no form of this command to restore the default largest packet size.
qllc largest-packet virtual-mac-addr max-size
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration commands. This address is written as a dotted triple of four-digit hexadecimal numbers. |
max-size | Maximum size, in bytes, of the SNA packet that can be sent or received on the X.25 interface configured for QLLC conversion. This value agrees with the value configured in the remote SNA device. The valid range is 0 through 1024. |
265 bytes
Interface configuration
SNA packets that are larger than the largest value allowed on the X.25 connection and are received on the LLC2 interface are segmented before being sent on the X.25 interface. When a segmented packet is received on the X.25 interface, it is passed immediately to the LLC2 interface, and no effort is made to wait for the segment to be completed.
When the remote X.25 device has a limit on the maximum total length of recombined X.25 segments it will support, you can use the qllc largest-packet command to ensure the length is not exceeded. For example, a device whose maximum SNA packet size is limited to 265 bytes might not be able to handle a series of X.25 packets that it has to recombine to make a 4, 8, or 17 KM SNA packet, such as one often encounters in an LLC2 environment.
You use the qllc largest-packet command in conjunction with the x25 map qllc and qllc srb commands.
Consult your IBM documentation to set the maximum packet size on the remote X.25 device.
In the following example, the maximum packet size that has been established for the virtual circuit is used as the maximum packet size that can be sent or received on the X.25 interface:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
qllc srb 0100.0000.0001 201 100
!
qllc partner 0100.0000.0001 4000.0101.0132
qllc xid 0100.0000.0001 01720001
qllc largest-packet 0100.0000.0001 521
qllc srb
x25 map qllc
x25 pvc qllc
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration commands. This address is written as a dotted triple of four-digit hexadecimal numbers. |
Disabled
Interface configuration
The qllc npsi-poll command is necessary only when the upstream device is a FEP running NPSI and the downstream device is a PU 2.0.
This command is necessary because in a Token Ring or RSRB environment the LAN attached devices start up by sending a null XID packet upstream. If the router forwards this null XID to an X.25-attached FEP, the FEP responds as if it were connecting to an PU2.1 device, and breaks the connection when the PU 2.0 next sends an XID Format 0 Type 2. The qllc npsi-poll command intercepts any null XID packet that the router receives on the LAN interface, and returns a null XID response to the downstream device. It continues to allow XID Format 3 and XID Format 0 packets through the X.25 device.
The following example facilitates a connection between a FEP running NPSI and a downstream PU 2.0.
qllc npsi-poll 0100.0000.0001
A dagger (†) indicates that the command is documented in another chapter.
qllc srb
sdlc qllc-prtnr †
x25 map qllc
x25 pvc qllc
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration commands. This address is written as a dotted triple of four-digit hexadecimal numbers. |
mac-addr | 48-bit MAC address of the Token Ring host that will communicate with the remote X.25 device. |
Disabled
Interface configuration
When the router receives an incoming call from the designated X.121 address, it opens an LLC2 connection with the device at the given MAC address. Both the MAC address of the Token Ring device and the virtual MAC address for the remote X.25 device with which it is to communicate are required in order for the router to initiate connections with the Token Ring device. This allows the Token Ring host to be permanently ready to accept a connection rather than requiring operator action at the host to initiate the connection with the X.25 device.
You must issue the qllc partner command for each remote X.25 device that will communicate with the local Token Ring host through this interface.
You use the qllc partner command in conjunction with the x25 map qllc and qllc srb commands.
In the following example, the qllc partner command is used to associate the virtual MAC address 0100.0000.0001, as defined in the previous x25 map qllc entry, with the MAC address of the Token Ring host that will communicate with the remote X.25 device:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
qllc srb 0100.0000.0001 201 100
!
qllc partner 0100.0000.0001 4000.0101.0132
qllc xid 0100.0000.0001 01720001
Related Commands
A dagger (†) indicates that the command is documented in another chapter.
qllc srb
sdlc qllc-prtnr †
x25 map qllc
x25 pvc qllc
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration commands. This address is written as a dotted triple of four-digit hexadecimal numbers. |
ssap | Source SAP value. It can be a decimal number in the range 2 through 254. |
dsap | Destination SAP value. It can be a decimal number in the range 2 through 254. |
The default source SAP value is 04.
The default destination SAP value is 04.
Interface configuration
A SAP can be viewed as a port through which a higher-layer application can communicate with its counterpart (peer) operating on another system. While the standard SAP value for IBM devices is 04, other values are allowed.
You use the qllc sap command in conjunction with the x25 map qllc and qllc srb interface configuration commands.
In the following example, source SAP and destination SAP values of 02 are specified for the remote X.25 device at the X.121 address 31370054065:
interface serial 0
x25 map qllc 31370054065 4000.0122.0001
qllc srb 9 100
qllc sap 4000.0122.0001 02 02
qllc srb
x25 map qllc
x25 pvc qllc
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration commands. It can be 1 to 15 digits long. |
srn | Source ring number. This value defines a virtual ring for all of the remote X.25 devices attached to the QLLC interface. Any number of QLLC conversion connections using the same X.25 serial interface can share a common source ring. However, this source ring must be a unique hexadecimal ring number within the source-bridged network. |
trn | Target ring number. It must be a virtual ring group that has been defined with the source-bridge ring-group global configuration command. If the router has only one Token Ring interface and is bridging from the remote X.25 devices to this interface, then trn is the number of the ring on that Token Ring interface. If the router has several Token Ring interfaces and interconnects them by means of the source-bridge ring-group command, then trn is the number of that virtual ring group, as assigned using the source-bridge ring-group global configuration command. |
QLLC conversion is not enabled.
Interface configuration
Use the qllc srb command to associate the ring number and bridge number that have been assigned to the interface with a virtual ring group of which the interface will be a part. The serial interface appears to be a ring, or source ring number, on a source-route bridge network, and ties in to the virtual ring group, or target ring number. The target ring number provides access to other real rings that have been designated using the source-bridge global configuration command. Note that you can configure QLLC conversion on a router containing no Token Ring interface cards, such as a router connecting a serial-attached device to an X.25 PDN.
The qllc srb command automatically turns on the LLC2 process with default values. To change any of the LLC2 parameters (described in the "LLC2 and SDLC Commands" chapter), apply their values to the serial interface that has been configured for QLLC conversion. This is done on the serial interface, even though LLC2 does not technically run on the serial interface, but on the virtual ring associated with the serial interface.
You use the qllc srb command in conjunction with the x25 map qllc command.
In the following example, the qllc srb command is used to define a virtual ring number of 201 for the remote X.25 device, and an actual or virtual ring number of 100 for the Token Ring interface:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
qllc srb 0100.0000.0001 201 100
source-bridge
source-bridge ring-group
source-bridge remote-peer
x25 map qllc
x25 pvc qllc
virtual-mac-addr | Virtual MAC address associated with the remote X.25 device, as defined using the x25 map qllc or x25 pvc qllc interface configuration command. This address is written as a dotted triple of four-digit hexadecimal numbers. |
xid | Combined XID IDBLK and XID IDNUM you are associating with the X.25 device at this X.121 address. This hexadecimal value must be four bytes (eight digits) in length. |
XID processing is not enabled.
Interface configuration
Most QLLC installations do not need the qllc xid configuration command. It is only needed if the remote X.25 device is not configured to send its own XID. This is only possible for a device that is attached via a PVC. Even so, most devices that are connected via X.25 will send their own XIDs. Use the qllc xid command when the Token Ring host requires login validation for security purposes and the remote X.25 device does not send an XID. The XID value is used to reply to XID requests received on the Token Ring (LLC2) side of the connection. XID requests and responses are usually exchanged before sessions are started. The XID response to the XID request from the Token Ring host will contain the information you configure using the qllc xid command. The host will check the XID response it receives with the IDBLK and IDNUM parameters (configured in VTAM). If they match, the Token Ring host will initiate a session with the router. If they do not match, the host will not initiate a session with the router.
You use the qllc xid command in conjunction with the x25 map qllc and the qllc srb commands.
In the following example, the X.25 device at X.121 address 31104150101 must use an XID IDBLK of 017 and XID IDNUM of 20001 to access the Token Ring host whose MAC address is associated with the remote X.25 device, as applied using the qllc partner command:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
qllc srb 0100.0000.0001 201 100
!
qllc partner 0100.0000.0001 4000.0101.0132
qllc xid 0100.0000.0001 01720001
qllc srb
x25 map qllc
x25 pvc qllc
Use the sdllc partner interface configuration command to enable device-initiated connections for SDLLC. This command must be specified for the serial interface that links to the serial line device. Use the no form of this command to cancel the original instruction.
sdllc partner mac-address sdlc-address
mac-address | 48-bit MAC address of the Token Ring host. |
sdlc-address | SDLC address of the serial device that will communicate with the Token Ring host. |
Disabled
Interface configuration
Both the MAC address of the Token Ring host and the SDLC serial line address are required to initiate connections with the Token Ring host.
The Token Ring host and the serial device communicate with each other through the router. Although the device is said to initiate connections, the router actually initiates connections with the Token Ring host on behalf of the serial device. As part of Cisco's SDLLC implementation, the serial device "thinks" that it is communicating with a host also on a serial line. It is actually the router that does all the frame and protocol conversions between serial and Token Ring devices.
There are two conditions under which a router will attempt to initiate a connection to a host on behalf of a serial device:
The router will continue trying once a minute to initiate a connection whenever one of these two conditions is met, until the host responds to its requests. When you no longer want the router to initiate connections with a host, use the no sdllc partner command.
In the following example, a serial device at SDLC address c2 wants to initiate a connection with a Token Ring host at MAC address 4000.0122.0001. The router initiates the connection on behalf of a serial device:
! sample global command
source-bridge ring-group 100
!
interface serial 0
! router initiates connections with Token Ring host at MAC address
! 4000.0122.0001 on behalf of serial device c2
sdllc partner 4000.0122.0001 c2
Use the sdllc ring-largest-frame interface configuration command to indicate the largest I-frame size that can be sent to or received from the LLC2 primary station. Use the no form of this command to return to the default.
sdllc ring-largest-frame value
value | Frame size in bytes. |
516 bytes
Interface configuration
Possible values for the value argument match those that are possible for the lf size of the various source-bridge remote-peer commands. You must ensure that your remote peer connection can support this largest frame size. Possible values for the value argument include 516, 1500, 2052, 4472, 8144, 11407, and 17800.
Faster screen updates to 3278-style terminals often can be obtained by allowing the Token Ring FEP to send as large a frame as possible and by allowing the router to segment the frame into multiple SDLC I-frames.
In the following example, the router can send or receive a frame as large as 11407 bytes from the LLC2 primary station. Any frames larger will be fragmented by the router:
! sample global command
source-bridge ring-group 100
!
interface serial 3
! largest frame sent or received on serial 3 is 11407 bytes
sdllc ring-largest-frame 11407
source-bridge remote-peer fst
source-bridge remote-peer interface
source-bridge remote-peer tcp
sdlc-address | Virtual MAC address associated with the remote SDLC device. |
ssap | Source SAP value. It must be in the range 1 through 254. |
dsap | Destination SAP value. It must be in the range 1 through 254. |
4
Interface configuration
You use the sdllc sap command in conjunction with the sdllc traddr interface configuration commands. A SAP can be viewed as a port through which a higher-layer application can communicate with its counterpart (peer) operating on another system. While the standard SAP value for IBM SNA devices is 4, and NetBIOS devices is xF0, other values are allowed.
In the following example, source SAP and destination SAP values of 2 are specified for the remote SDLC device at the SDLC address C1 02 02:
interface Serial0
sdllc sap C1 02 02
Use the sdllc sdlc-largest-frame interface configuration command to indicate the largest information frame (I-frame) size that can be sent or received by the designated SDLC station. Use the no form of this command to return to the default value.
sdllc sdlc-largest-frame address value
address | Address of the SDLC station that will communicate with the Token Ring host. |
value | Largest frame size that can be sent or received by this SDLC station. |
265 bytes
Interface configuration
Most SDLC devices are limited to frames of 265 bytes. I-frames received from the Token Ring station that are larger than this size will be properly fragmented.
In the following example, the router can send or receive a frame as large as 265 bytes (the default) from the SDLC station at address c6. Any frames larger will be fragmented by the router.
! sample global command
source-bridge ring-group 100
!
interface serial 4
! largest frame sent or received on serial 4 is 265 bytes
sdllc sdlc-largest-frame c6 265
Use the sdllc traddr interface configuration command to enable the use of SDLLC media translation on a serial interface. The address specified is a MAC address to be assigned to the serial station. Use the no form of this command to disable SDLLC media translation on the interface.
sdllc traddr xxxx.xxxx.xx00 lr bn tr
xxxx.xxxx.xx00 | MAC address to be assigned to the serial interface. |
lr | SDLLC virtual ring number. |
bn | SDLLC bridge number. |
tr | SDLLC target ring number. |
Disabled
Interface configuration
Every control unit hooked off the serial line requires a virtual Token Ring MAC address (VTRA).This usually is assigned by the system administrator as a locally administered address (unique across the network).
When you enable SDLLC Media Translation by specifying the sdllc traddr command on a serial interface, you must specify a virtual Token Ring address (VTRA) for each serial station attached to the serial line. The last two hexadecimal digits. (that is, the last byte) of the VTRA must be 00. The router uses this byte to represent the SDLC address of a station on the serial link. That is, addresses in the range xxxx.xxxx.xx00 to xxxx.xxxx.xxFF are reserved for use by the router. It is very important that you adhere to this addressing requirement. If you do not, there may be a conflict between the VTRA and the addresses reserved by the router for the SDLC link.
The variables lr, bn, and tr represent the SDLLC virtual ring number, bridge number, and target ring number, respectively, that you assign to the interface. In design, the serial interface appears to be a ring, lr, on a source-route bridged network, and ties in through the bridge, bn, to the virtual ring-group, tr. This provides access to other, real rings through remote source-route bridging source-bridge remote-peer commands. Note that SDLLC can be configured on a router containing no Token Ring interface cards.
The sdllc traddr command automatically turns on the LLC2 process with default values. To change any of the LLC2 parameters, specify their values on the serial interface that is being enabled for SDLLC. This is done on the serial interface, even though LLC2 does not technically run on the serial interface, but on the SDLLC virtual ring associated with the serial interface. LLC2 commands can be configured after specifying the sdllc traddr command.
In the following example, SDLLC media translation is enabled off the serial 0 interface to a serial station at MAC address 0110.2222.3300. The SDLLC virtual ring number is 8, the bridge number is 1, and the target ring number is 100:
! global command to apply commands to the ring group
source-bridge ring-group 100
! remote peer at IP address 131.108.1.1 belongs to ring group 100 and uses
! tcp as the transport
source-bridge remote-peer 100 tcp 131.108.1.1
source-bridge remote-peer 100 tcp 131.108.2.2
!
interface serial 0
encapsulation sdlc-primary
! establish address of SDLC station off serial-0 as c1
sdlc address c1
! enable SDLLC media translation to serial station 0110.2222.3300
! on virtual ring 8, bridge 1, to target ring 100
sdllc traddr 0110.2222.3300 8 1 100
sdllc sap
source-bridge remote-peer fst
source-bridge remote-peer interface
source-bridge remote-peer tcp
Use the sdllc xid interface configuration command to specify an eXchanged ID (XID) value appropriate for the designated SDLC station associated with this serial interface. Use the no form of this command to disable XID processing for this address.
sdllc xid address xxxxxxxx
address | Address of the SDLC station associated with this interface. |
xxxxxxxx | XID the router will use to respond to XID requests the router receives on the Token Ring (LLC2) side of the connection. This value must be 4 bytes (8 digits) in length and is specified with hexadecimal digits. |
Disabled
Interface configuration
XID requests and responses are usually exchanged before sessions are started. Be sure that the XID value configured on the router matches the IDBLK and IDNUM parameters configured on the host. The XID response to an XID request from the Token Ring host will contain the information you configured in the sdllc xid command. The host will check the XID response it receives with the IDBLK and IDNUM parameters (that are configured in the VTAM). If they match, the Token Ring host will initiate a session with the router. If they do not match, the host will not initiate a session with the router.
The following example specifies an XID value of 01720002 at address c2:
! sample global command
source-bridge ring-group 100
!
interface serial 0
! sdllc exchange identification value of 01720002 at address c2
sdllc xid c2 01720002
Use the show interfaces privileged EXEC command to display the SDLC information for a given SDLC interface.
show interfacesThis command has no arguments or keywords.
Privileged EXEC
The following is sample output from the show interfaces command for an SDLC primary interface supporting the SDLLC function:
Router# show interfaces
Serial 0 is up, line protocol is up
Hardware is MCI Serial
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation SDLC-PRIMARY, loopback not set
Timers (msec): poll pause 100 fair poll 500. Poll limit 1
[T1 3000, N1 12016, N2 20, K 7] timer: 56608 Last polled device: none
SDLLC [ma: 0000.0C01.14--, ring: 7 bridge: 1, target ring: 10
largest token ring frame 2052]
SDLC addr C1 state is CONNECT
VS 6, VR 3, RCNT 0, Remote VR 6, Current retransmit count 0
Hold queue: 0/12 IFRAMEs 77/22 RNRs 0/0 SNRMs 1/0 DISCs 0/0
Poll: clear, Poll count: 0, chain: p: C1 n: C1
SDLLC [largest SDLC frame: 265, XID: disabled]
Last input 00:00:02, output 00:00:01, output hang never
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
Five minute input rate 517 bits/sec, 30 packets/sec
Five minute output rate 672 bits/sec, 20 packets/sec
357 packets input, 28382 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
926 packets output, 77274 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets, 0 restarts
2 carrier transitions
Table 26-1 shows the fields relevant to all SDLC connections.
| Field | Description |
|---|---|
Timers (msec) | List of timers in milliseconds. |
poll pause, fair poll, Poll limit | Current values of these timers, as described in the individual commands in this chapter. |
T1, N1, N2, K | Current values for these variables, as described in the individual commands in this chapter. |
Table 26-2 shows other data given for each SDLC secondary configured to be attached to this interface.
| Field | Description |
|---|---|
addr | Address of this secondary. |
State | Current state of this connection. The possible values are:
|
VS | Sequence number of the next information frame this station sends. |
VR | Sequence number of the next information frame from this secondary that this station expects to receive. |
RCNT | Number of correctly sequenced I-frames received when the router was in a state in which it is acceptable to receive I-frames. |
Remote VR | Last frame transmitted by this station that has been acknowledged by the other station. |
Current retransmit count | Number of times the current I-frame or sequence of I-frames has been retransmitted. |
Hold queue: | Number of frames in hold queue/Maximum size of hold queue. |
IFRAMEs, RNRs, SNRMs, DISCs | Sent/received count for these frames. |
Poll: | "Set" if this router has a poll outstanding to the secondary; "clear" if it does not. |
Poll count: | Number of polls, in a row, given to this secondary at this time. |
chain: | Shows the previous (p) and next (n) secondary address on this interface in the round robin loop of polled devices. |
Use the show qllc EXEC command to display the current state of any QLLC connections.
show qllcThis command has no arguments or keywords.
Privileged EXEC
The following is sample output from the show qllc command.
Router# show qllc
QLLC Connections:
Serial2: 1000.5a35.3a4f->1000.5a59.04f9. SAPs 4 4. Rings Src 200, Tgt 100.
State Connect
Remote DTE 1002. QLLC Protocol State NORMAL lci 1 (PVC)
In the display, the first two lines of the show qllc command show that there is a QLLC session between a Token Ring device and an X.25 remote device. The X.25 device has a virtual MAC address of 100.5a35.3a4f with a SAP of 04. It is using a PVC with logical channel number 1. The Token Ring device has a MAC address of 1000.5a59.04f9 with a SAP of 04. The state of the QLLC session is CONNECTED.
Table 26-3 describes the fields shown in the display.
| Field | Description |
|---|---|
Serial2 | Serial interface for the X.25 link. |
1000.5a35.3a4f | Virtual MAC address for the X.25 attached device. |
1000.5a59.04f9 | MAC address of the Token Ring attached device with which the X.25 attached device is communicating. This device might be on a local Token Ring or attached via SRB or RSRB. |
SAPs 4 4 | Source SAP value at the virtual MAC address and destination SAP value at the Token Ring station. |
Rings Src 200 | Ring number for the source virtual ring defined by the qllc srb command. |
Tgt 100 | Ring number for the target virtual ring defined by the source-bridge ring-group command. |
| State | State of the QLLC-LLC2 conversion. This can be any of the following: |
DISCONNECT | No connection exists. |
NET DISC WAIT | The X.25 device is disconnecting. The QLLC conversion is waiting for the Token Ring device to disconnect. |
QLLC DISC WAIT | The Token Ring device is disconnecting. The QLLC conversion is waiting for the X.25 device to disconnect. |
QLLC PRI WAIT | Connection is being established. The Token Ring device is ready to complete the connection, and the router is establishing the QLLC connection with the X.25 device. |
NET CONTACT REPLY WAIT | Remote X.25 device is a FEP, and has made contact with the router. The router is attempting to reach Token Ring device. |
QLLC SEC WAIT | Connection is being established. |
NET UP WAIT | Connection is being established. QLLC connection to X.25 device has been established; awaiting completion on the connection to the Token Ring attached device. |
CONNECT | Connections from the router to X.25 and Token Ring devices are established. Data can flow end to end. |
Remote DTE 1002 | X.121 address of X.25 connected device. |
QLLC Protocol State | State of the QLLC protocol between the router and the X.25 attached device. These states are different from the state of the underlying X.25 virtual circuit. The following are possible values: |
ADM | Asynchronous Disconnected Mode. |
SETUP | Router has initiated QLLC connection, awaiting confirmation from the X.25 device. |
RESET | Router has initiated QLLC Reset, awaiting confirmation from the X.25 device. |
DISCONNECTING | Router has initiated QLLC Disconnect, awaiting confirmation from the X.25 device. |
NORMAL | QLLC connection has been completed. SNA data can be transmitted and received. |
lci 1 (PVC) | Logical channel number used on the X.25 interface. |
Use the show sdllc local-ack privileged EXEC command to display the current state of any current Local Acknowledgment connections, as well as any configured Passthrough Rings.
show sdllc local-ackThis command has no arguments or keywords.
Privileged EXEC
The following is sample output from the show sdllc local-ack command:
Router# show sdllc local-ack
local 1000.5a59.04f9, lsap 04, remote 4000.2222.4444, dsap 04
llc2 = 1798136, local act state = connected
Passthrough Rings: 4 7
In the display, the first two lines of the show sdllc local-ack command show that there is a Local Acknowledgment session between two Token Ring devices. The device on the local ring has a MAC address of 1000.5a59.04f9 with a SAP of 04. The remote device has a MAC address of 4000.2222.4444 with a SAP of 04. The state of the Local Acknowledgment session is connected.
The Passthrough Rings display is independent of the rest of the show sdllc local-ack command. The Passthrough Rings display indicates that there are two rings, 4 and 7, configured for Passthrough. This means that stations on these rings will not have their sessions locally acknowledged but will instead have their acknowledgments end-to-end.
Table 26-4 describes significant fields shown in the display.
| Field | Description |
|---|---|
local | MAC address of the local Token Ring station with which the router has the LLC2 session. |
lsap | Local SAP value of the Token Ring station with which the router has the LLC2 session. |
remote | MAC address of the remote Token Ring station on whose behalf the router is providing acknowledgments. The remote Token Ring station is separated from the router via the TCP backbone. |
dsap | Destination SAP value of the remote Token Ring station on whose behalf the router is providing acknowledgments. |
llc2 | Pointer to an internal data structure used by technical support staff for debugging. |
local-ack state: | The current state. Possible values are as follows:
|
Passthrough Rings | Ring number of the start ring and destination ring for the two IBM machines when you do not have local acknowledgment for LLC2 configured for your routers using RSRB. |
Use the source-bridge fst-peername global configuration command to set up a Fast-Sequenced Transport (FST) peer name. Use the no form of this command to disable the IP address assignment.
source-bridge fst-peername local-interface-address
local-interface-address | IP address to assign to the local router. |
Disabled
Global configuration
Using this command is the first step to configuring a remote source-route bridge to use FST.
The following example shows the use of the source-bridge fst-peername command:
source-bridge fst-peername 150.136.64.98
This command has no arguments or keywords.
QLLC local acknowledgment is disabled.
Global configuration
In a remote source-route bridged topology, QLLC local acknowledgment is used to configure the QLLC conversion router (connecting the remote X.25 devices) to exchange local acknowledgment information with the Token Ring router (on the Token Ring side of the cloud). (This Token Ring router has been configured for LLC2 local acknowledgment using the source-bridge remote peer tcp local-ack command.)
You only have to issue the source-bridge qllc-local-ack command on the QLLC conversion router. When this command is issued, all of the router's QLLC conversion sessions are locally acknowledged at the Token Ring interface of the Token Ring router with which it is communicating using QLLC conversion.
The following configuration indicates that the local router (131.108.2.2) QLLC conversion sessions will be locally acknowledged at the remote router:
source-bridge ring-group 100
source-bridge remote-peer 100 tcp 131.108.1.1 local-ack
source-bridge remote-peer 100 tcp 131.108.2.2
source-bridge qllc-local-ack
source-bridge ring-group
source-bridge remote-peer
Use the source-bridge remote-peer fst global configuration command to specify a Fast-Sequenced Transport (FST) encapsulation connection. Use the no form of this command to disable the previous assignments.
source-bridge remote-peer ring-group fst ip-address [lf size] [version number]
ring-group | Ring group number. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 through 4095. |
ip-address | IP address of the remote peer with which the router will communicate. |
lf size | (Optional) Maximum size frame to be sent to this remote peer. The router negotiates all transit routes down to this size or lower. Use this argument to prevent timeouts in end hosts by reducing the amount of data they have to transmit in a fixed interval. The legal values for this argument are 516, 1500, 2052, 4472, 8144, 11407, and 17800 bytes. |
version number | (Optional) Forces RSRB protocol version number for the remote peer. Because all FST peers support version 2 RSRB, the version keyword is always specified. |
No FST encapsulation connection is specified.
Global configuration
The two peers using the serial-transport method will only function correctly if there are routers/bridges at the end of the serial line that have been configured to use the serial transport. The peers must also belong to the same ring group.
In the following example the source-bridge fst-peername command specifies an IP address of 150.136.64.98 for the local router. The source-bridge ring-group command assigns the router to a ring group. The source-bridge remote-peer fst command specifies ring group number 100 for the remote peer at IP address 150.136.64.97.
source-bridge fst-peername 150.136.64.98
source-bridge ring-group 100
source-bridge remote-peer 100 fst 150.136.64.97 version 2 RSRB
source-bridge
source-bridge fst-peername
source-bridge remote-peer interface
source-bridge remote-peer tcp
Use the source-bridge remote-peer interface global configuration command when specifying a point-to-point direct encapsulation connection. Use the no form of this command to disable previous interface assignments.
source-bridge remote-peer ring-group interface interface-name [mac-address] [lf size]
ring-group | Ring group number. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 through 4095. |
interface-name | Name of the router's serial interface over which to send source-route bridged traffic. |
mac-address | (Optional) MAC address for the interface you specify using the interface-name argument. This argument is required for nonserial interfaces. You can obtain the value of this MAC address by using the show interfaces command, and then scanning the display for the interface specified by interface-name. |
lf size | (Optional) Maximum size frame to be sent to this remote peer. The router negotiates all transit routes down to this size or lower. This argument is useful in preventing timeouts in end hosts by reducing the amount of data they have to transmit in a fixed interval. The legal values for this argument are 516, 1500, 2052, 4472, 8144, 11407, and 17800 bytes. |
No point-to-point direct encapsulation connection is specified.
Global configuration
Use this command to identify the interface over which to send source-route bridged traffic to another router/bridge in the ring group. A serial interface does not require that you include a MAC-level address; all other types of interfaces do require MAC addresses.
It is possible to mix all types of transport methods within the same ring group.
The following example shows how to send source-route bridged traffic over interfaces serial 0 and Ethernet 0:
! send source-route bridged traffic over serial 0
source-bridge remote-peer 5 interface serial 0
! specify MAC address for source-route bridged traffic on Ethernet 0
source-bridge remote-peer 5 interface Ethernet 0 0000.0c00.1234
show interfaces
source-bridge
source-bridge remote-peer fst
source-bridge remote-peer tcp
Use the source-bridge remote-peer tcp global configuration command to identify the IP address of a peer in the ring group with which to exchange source-bridge traffic using TCP. Use the no form of this command to remove a remote peer for the specified ring group.
source-bridge remote-peer ring-group tcp ip-address [lf size] [local-ack] [priority]
ring-group | Ring group number. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 through 4095. |
ip-address | IP address of the remote peer with which the router will communicate. |
lf size | (Optional) Maximum size frame to be sent to this remote peer. The router negotiates all transit routes down to this size or lower. Use this argument to prevent timeouts in end hosts by reducing the amount of data they have to transmit in a fixed interval. The valid values for this argument are 516, 1500, 2052, 4472, 8144, 11407, and 17800 bytes. |
local-ack | (Optional) LLC2 sessions destined for a specific remote peer are to be locally terminated and acknowledged. Local Acknowledgment should be used for LLC2 sessions going to this remote peer. |
priority | (Optional) Enables prioritization over a TCP network. You must specify the keyword local-ack earlier in the same source-bridge remote-peer command. The keyword priority is a prerequisite for features such as SNA class of service and SNA LU address prioritization over a TCP network. |
No IP address is identified.
Global configuration
If you configure one peer for LLC2 local acknowledgment, you need to configure both peers for LLC2 local acknowledgment. If only one peer is so configured, unpredictable (and undesirable) results will occur.
The two peers using the serial-transport method will only function correctly if there are routers/bridges at the end of the serial line that have been configured to use the serial transport. The peers must also belong to the same ring group.
In the following example, the remote peer with IP address 131.108.2.291 belongs to ring group 5. It also uses LLC2 Local Acknowledgment, priority, and RSRB protocol version 2:
! identify the ring group as 5
source-bridge ring-group 5
! remote peer at IP address 131.108.2.291 belongs to ring group 5, uses
! tcp as the transport, is set up for local acknowledgment, uses
! priority, and uses RSRB protocol form of this command 2
source-bridge remote-peer 5 tcp 131.108.2.291 local-ack priority form of this command 2
The following example shows how to locally administer and acknowledge LLC2 sessions destined for a specific remote peer:
! identify the ring group as 100
source-bridge ring-group 100
! remote peer at IP address 1.1.1.1 does not use local acknowledgment
source-bridge remote-peer 100 tcp 1.1.1.1
! remote peer at IP address 1.1.1.2 uses local acknowledgment
source-bridge remote-peer 100 tcp 1.1.1.2 local-ack
!
interface tokenring 0
source-bridge 1 1 100
Sessions between a device on Token Ring 0 that must go through remote peer 1.1.1.2 use local acknowledgment for LLC2, but sessions that go through remote peer 1.1.1.1 do not use local acknowledgment (that is, they "pass through").
source-bridge
source-bridge remote-peer fst
source-bridge remote-peer interface
Use the source-bridge ring-group global configuration command to define or remove a ring group from the router configuration. Use the no form of this command to cancel previous assignments.
source-bridge ring-group ring-group
ring-group | Ring group number. The valid range is 1 through 4095. |
No ring group is defined.
Global configuration
To configure a source-route bridge with more than two network interfaces, the ring-group concept is used. A ring group is a collection of Token Ring interfaces in one or more routers that are collectively treated as a virtual ring. The ring group is denoted by a ring number that must be unique for the network. The ring group's number is used just like a physical ring number, showing up in any route descriptors contained in packets being bridged.
To configure a specific interface as part of a ring group, its target ring number parameter is set to the ring group number specified in this command. You should not use the number 0, because it is reserved to represent the local ring.
In the following example, multiple Token Rings are source-route bridged to one another through a single router/bridge. These Token Rings are all part of ring group 7.
! all token rings attached to this bridge/router are part of ring group 7
source-bridge ring-group 7
!
interface tokenring 0
source-bridge 1000 1 7
!
interface tokenring 1
source-bridge 1001 1 7
!
interface tokenring 2
source-bridge 1002 1 7
!
interface tokenring 3
source-bridge 1003 1 7
source-bridge
Use the source-bridge sdllc-local-ack global configuration command to activate local acknowledgment for SDLLC sessions on a particular interface. Use the no form of this command to deactivate local acknowledgment for SDLLC sessions.
source-bridge sdllc-local-ackThis command has no keywords or arguments.
Disabled
Global configuration
This command must be issued only on the router with the serial interface(s). Once the command is issued, all SDLLC sessions between the two routers will be locally acknowledged. You cannot selectively choose which SDLLC sessions are to be locally acknowledged and which are not. Also, local acknowledgment is not supported when the LLC2 station is attached to Ethernet rather than to Token Ring.
The following example activates local acknowledgment for SDLLC sessions:
source-bridge ring-group 100
source-bridge remote-peer 100 tcp 131.108.1.1 local-ack
source-bridge remote-peer 100 tcp 131.108.2.2
source-bridge sdllc-local-ack
virtual-mac-addr | Virtual MAC address you are associating with the X.25 device at this X.121 address. The router will accept explorer and data packets destined for this MAC address. It can be from 1 to 15 digits long. |
x121-addr | X.121 address of the remote X.25 device you are associating with this virtual MAC address. It can be from 1 to 15 digits long. |
No association is made.
Interface configuration
The central notion that binds the QLLC conversion interface to the X.25 and SRB facilities is the X.25 address map. For each remote client an X.121 address is associated with a virtual MAC address. The rest of the configuration is specified by using the virtual Token Ring address to refer to the connection.
When a Token Ring devices wishes to open communications with another device, it will send the request to the address it knows, which is the MAC address. The router accepts this connection request and must transform it into a known X.121 address. The x25 map qllc command matches the MAC address with the X.121 address.
You must enter a mapping for each X.25 device with which the router will exchange traffic.
All QLLC conversion commands use the virtual-mac-addr parameter that you define with the x25 map qllc command to refer to the connection.
You use the x25 map qllc command in conjunction with the qllc srb command.
In the following example, the x25 map qllc command is used to associate the remote X.25 device at X.121 address 31104150101 with the virtual MAC address 0100.000.0001:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
qllc srb 0100.0000.0001 201 100
circuit | PVC you are associating with the virtual MAC address. This must be lower than any number assigned to switched virtual circuits. |
virtual-mac-addr | Virtual MAC address you are associating with the X.25 device at this PVC. The router will accept explorer and data packets destined for this MAC address. This virtual MAC address must match the virtual MAC address you specified using the x25 map qllc command. |
No association is made.
Interface configuration
When a Token Ring device wishes to communicate with another device, it will send the request to the address it knows, which is the MAC address. The router accepts this connection request and transforms it into the known X.121 address and virtual circuit. You must use the x25 map qllc command to specify the required protocol-to-X.121 address mapping before you use the x25 pvc qllc command. The x25 map qllc command associates the MAC address with address with the X.121 address, and the x25 pvc qllc command further associates that address with a known pvc.
You use the x25 pvc command in conjunction with the x25 map qllc and qllc srb commands.
In the following example, the x25 pvc qllc command associates the virtual MAC address 0100.0000.0001, as defined in the previous x25 map qllc command entry, with PVC 3:
interface serial 0
encapsulation x25
x25 address 31102120100
x25 map qllc 0100.0000.0001 31104150101
x25 pvc 3 qllc 0100.0000.0001
qllc srb
x25 lic
x25 loc
x25 ltc
x25 map qllc
Posted: Mon Oct 21 11:17:50 PDT 2002
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