This chapter describes the SDLC configuration and monitoring commands. It contains these sections:
About SDLC Configuration and Monitoring Commands
Accessing the SDLC Configuration Environment
Accessing the SDLC Monitoring Environment
SDLC Commands
For instructions on configuring SDLC, see Using the DLSw Protocol.
About SDLC Configuration and Monitoring Commands
SDLC configuration commands are available at the SDLC # Config> prompt, where # identifies the interface you specify with the network command. Changes made to the router's configuration do not take effect immediately, but become part of the router's non-volatile configuration memory when the router restarts.
Conversely, SDLC monitoring commands entered within the SDLC monitoring module take effect immediately. However, changes made with monitoring commands do not become part of the router's non-volatile configuration.
When the router restarts, the configuration stored in non-volatile configuration memory supersedes the effects of monitoring commands.
Monitoring consists of these actions:
Monitoring the protocols and network interfaces the router is using.
Making real-time changes to the SDLC configuration without permanently affecting the router's non-volatile configuration memory.
Displaying ELS (Event Logging System) messages relating to router activities and performance.
* config
Config>
If the Config> prompt does not appear immediately, press Return again.
Config>network 3
SDLC 3 Config>
* monitor
Monitor>
Monitor> network 3
SDLC Console
SDLC-3>
Self-Test Self-Test Maintenance
Nt Nt Interface CSR Passed Failed Failed
3 FR SDLC/1 80000000 1 0 0
SDLC MAC/data-link on Quad Serial Line interface.
Level converter: RS-232/V.35 Adapter cable: RS-232 DCEV.24 circuit: 105 106 107 108 109
Nicknames: RTS CTS DSR DTR DCD
RS-232 DCE: CA CB CC CD CF
State: OFF OFF OFF OFF OFF
Line speed (configured): 9.615 Kbps
Last port reset: 1 minute, 24 seconds ago
Input frame errors:
CRC error 0 alignment (byte length) 0
Too short (< 2 bytes) 0 Too long (> 2051 bytes) 0
aborted frame 0 DMA/FIFO overrun 0
Output frame errors:
DMA/FIFO Underrun error 0 Outputs aborts sent 0
The following six parameters appear only if a cable is connected, and varies according to cable type.
SDLC Commands
This section summarizes and describes SDLC configuration and monitoring commands.
Table 2 lists SDLC configuration and monitoring commands and their functions.
| Command | Function |
| Add [C] [M] | Adds an SDLC link station. |
| Clear [M] | Clears link or link station counters. |
| Delete [C] [M] | Removes an SDLC link station. |
| Disable [C] [M] | Prevents connections to an SDLC link station. |
| Enable [C] [M] | Allows connections to an SDLC link station. |
| List [C] [M] | Displays SDLC link station configurations and link counters. |
| Set [C] [M] | Configures specific interface and link station information. |
| Test [M] | Performs an echo test on a link station. |
| Exit [C] [M] | Exits the SDLC configuration or monitoring environment. |
Add [C] [M]
Use the SDLC stations that you configure in DLSw or use the add station command to explicitly set up SDLC stations in the following situations:
The following defaults for SDLC stations are not satisfactory:
-Maximum BTU is maximum allowable by interface
-Tx and Rx Windows are 7 for MOD 8, 127 for MOD 128
The SNA devices on the link are of mixed node types.
You want to use the group poll feature.
You want greater flexibility and control by using the SDLC monitoring commands.
The attached stations are of type PU2 if the router's link role is primary or secondary.
The attached stations are of type T2.1 if the router's link role is negotiable.
add station
Enter station address (in hex) [C2]?
Enter station name [SDLC_C2]?
Include station in group poll list ([Yes] or No):
Enter max packet size [2048]?
Enter receive window [7]?
Enter transmit window [7]?
Enter PU2 or T2.1 node type [PU2]?
|
Enter station address
| The station's SDLC address in the range 01 to FE. This station address must correspond to the station address added using the add sdlc command in the DLSw configuration environment. |
|
Enter station name
| The name of the SDLC station (maximum characters is 8). |
|
Include station in group poll list
|
Determines whether or not to include the station in the group poll list for this link. The SDLC software supports the IBM 3174 group poll (GP3174) feature when the router is operating in a local secondary SDLC link role and the adjacent SDLC primary device, typically and IBM mainframe, is suitably configured. You must supply a valid, nonzero group poll address on the link using the set link group-poll command in order for station inclusion to have an effect. |
|
Enter max packet size
|
The maximum packet size that the router can send to or receive from the remote link station. This value cannot be greater than that specified for the link with set link frame-size. |
|
Enter receive window
| The maximum number of packets that the router can receive without sending a response. |
|
Enter transmit window
| The maximum number of packets that the router can transmit without receiving a response. |
|
Enter PU2 or T2.1 node type
| The node type, either PU2 (PU 2.0) or T2.1 (PU 2.1). |
Clear [M]
Clears counters for the end station.
station name or address or all
Clears counters for either a specific end station or all end stations. You can display these counters using the list station counters command.
Delete [C] [M]
Removes the specified end station from the SDLC configuration.
When used in the monitoring environment, this command terminates any SDLC session in progress.
Syntax: delete station name or address
Example:delete station c1
Disable [C] [M]
Prevents the router from making connections with a SDLC link or station.
When used in the monitoring environment, disable link also terminates all existing connections on the link.
station name or address
Prevents establishment of an SDLC session to the specified station.
When used in the monitoring environment, disable station also terminates any existing SDLC session.
Enable [C] [M]
Both links and stations are enabled upon creation. You need to enable them if you previously disabled them.
station name or address
Allows connections to the specified end station.
List [C] [M]
In the SDLC configuration process, list displays configuration information on one or all SDLC link stations. In the monitoring process, list displays statistics specific to the data-link layer and the interface.
Link configuration for: LINK_2 (ENABLED)
Role: SECONDARY Type: POINT-TO-POINT
Duplex: FULL Modulo: 8
Idle state: FLAG Encoding: NRZ
Clocking: EXTERNAL Frame Size: 2048
Speed: 0 Group Poll: F3
Cable: V.36 DTE
Timers: XID/TEST response: 2.0 sec
SNRM response: 2.0 sec
Poll response: 0.5 sec
Inter-poll delay: 0.2 sec
RTS hold delay: DISABLED
Inter-frame delay: DISABLED
Inactivity timeout: 30.0 sec
Counters: XID/TEST retry: 4
SNRM retry: 6
Poll retry: 10
station all or address or link station name
Displays information for the specified SDLC link station or for all link stations.
Address Name Status Max BTU Rx Window Tx Window Node Type
------- -------- ---------- ------- --------- --------- ----------
C1(00) SDLC_C1 ENABLED 2048 7 7 T2.1
Address Name Status Max BTU Rx Window Tx Window Node Type
------- -------- ---------- ------- --------- --------- ----------
C1(00) SDLC_C1 ENABLED 2048 7 7 T2.1
C2(00) SDLC_C2 DISABLED 2048 7 7 PU 2
|
Address
| The address of the SDLC link station, and optionally, its corresponding group poll address in parentheses. The group poll address appears when you have configured the station for group poll list inclusion, and is the address established for the overall SDLC link. The group poll address is only meaningful when it is nonzero. A zero address indicates that the station is configured for group inclusion, but a valid link group address is not configured. |
|
Name
| The name of the SDLC link station. |
|
Status
| The status of the SDLC link station, enabled or disabled. |
|
Max BTU
|
The frame size limit of the station. It must not be larger than the maximum Basic Transmission Unit (BTU) packet size you configured with set link frame-size. |
|
Rx Window
| The size of the receive window. |
|
Tx Window
| The size of the transmit window. |
|
Node Type
| The SNA peripheral node type, either PU2 (PU 2.0) or T2.1 (PU 2.1). |
link counters
Displays information for the SDLC counters since the last router restart or the last clear counters.
Link counters for: LINK_2 (ENABLED)
I-Frames I-Bytes Re-Xmit UI-Frames UI-Bytes
--------- --------- --------- --------- ---------
Send 0 0 0 0 0
Recv 0 0 0 0
RR RNR REJ UP
--------- --------- --------- ---------
Send 0 0 0 0
Recv 0 0 0 0
station all or address or link station name
Displays the status of the specified SDLC link station or all stations.
Address Name Status Max BTU Rx Window Tx Window Node Type
------- -------- ---------- ------- --------- --------- ----------
C1(00) SDLC_C1 IDLE 2048 7 7 PU 2
C2(00) SDLC_C2 ENABLED 2048 7 7 PU 2
list station c1
Address Name Status Max BTU Rx Window Tx Window Node Type
------- -------- ---------- ------- --------- --------- ----------
*C1(00) SDLC_C1 IDLE 2048 7 7 PU 2
|
Address
|
The address of the SDLC link station, and optionally, its corresponding group poll address in parentheses. The group poll address appears when you have configured the station for group poll list inclusion, and is the address established for the overall SDLC link. The group poll address is only meaningful when it is nonzero. A zero address indicates that the station is configured for group inclusion, but a valid link group address is not configured. An * (asterisk) next to stations means that you added the station in the DLSw configuration process using the add sdlc command. |
|
Name
| The name of the SDLC link station. |
|
Status
|
The status of the SDLC link station: Enabled Enabled, but not allocated Idle Allocated, but not in use Connected Connected Disconnected Disconnected Connecting Connection establishment in progress Discnectng Disconnection in progress Recovering Attempting to recover from a temporary data link error |
|
Max BTU
| The frame size limit of the station. This frame size must not be larger than the maximum Basic Transmission Unit (BTU) packet size you configured with set link frame-size. |
|
Rx Window
| The size of the receive window. |
|
Tx Window
| The size of the transmit window. |
|
Node Type
| The SNA peripheral node type, either PU2 (PU 2.0) or T2.1 (PU 2.1). |
station name or address counters
Displays frame transmit and receive counts for the specified link station.
Example: list station c1 counters
Counters for: SDLC_C1 , address C1 (ENABLED)
I-Frames I-Bytes Re-Xmit UI-Frames UI-Bytes XID-Frames
-------- ------- -------- --------- -------- ----------
Send 569 88870 0 0 0
Recv 345 4804 0 0 0
RR RNR REJ TEST SNRM DISC
-------- ------ -------- --------- -------- ----------
Send 4779 0 0 1 1 0
Recv 4443 0 0 1 0 0
UA DM FRMR
-------- ------- --------
Send 0 0 0
Recv 0 0 0
Set [C] [M]
In the SDLC configuration process, set configures specific information for one or all SDLC link stations.
In the SDLC monitoring process, set dynamically configures information for one or all SDLC link stations without affecting the router's configuration memory. You can issue set only on disabled links or stations. Not all parameters are available in the monitoring process. Enter ? after you type a command to display the available parameters.
All time values are in seconds, with a 100ms resolution.
set link cable rs-232 dte
link clocking internal or external or mixed
Configures the SDLC link's clocking. To connect to a modem or DSU, set clocking to external. To connect directly to another DTE device, use a DCE cable and set the clocking to internal. If the modem provides the receive clock lines and expects the transmit clock line, use mixed. For internal and mixed clocking, you must enter set link speed to configure a clock speed in the range 0 to 6250000 bits per second.
Example: set link clocking internal
link duplex full or half
Configures the SDLC link for full-duplex or half-duplex modem control.
link encoding nrz or nrzi
Configures the SDLC transmission encoding scheme as NRZ (Non-Return to Zero) or NRZI (Non-Return to Zero Inverted). NRZ is the default.
Example: set link encoding nrz
link frame-size
Configures the maximum size of the frames that can be transmitted and received on the data link. The valid entries are 576 to 18000. The default is 2048.
You must set the link frame size greater than the maximum packet size configured with set station max packet. Otherwise, the router automatically resets the max packet size to the link frame size, and issues the following ELS message:
SDLC.054: nt 3 SDLC/0 Stn C4-MaxBTU too large for Link adjusted (4096->2048)
set link frame-size
Frame size in bytes (576 - 18000) [2048]?
The SDLC software supports the IBM 3174 group poll (GP3174) feature when the router is configured for a local secondary SDLC link role and the adjacent SDLC primary device, typically and IBM mainframe, is suitably configured. The router ignores this value when it is in local primary mode.
The add station or set station group-inclusion commands include a station in the group poll list. The list station monitoring command displays a parenthesized group address, which confirms the inclusion.
Enter group poll address (in hex) [00]? F3
Group poll support enabled
link inactivity #-of-seconds
Applies to stations that have been activated (NRM/E) by the SDLC protocol. If the station does not receive any frames for the number of seconds specified, the station enters into a recovery state. The range is 0 to 7200 seconds. The default is 30 seconds. A 0 (zero) allows the station to remain idle indefinitely.
Enter secondary link station inactivity timeout [30.0]?
Example: set link inter-frame delay
Transmit Delay Counter [0]?
Note: When you change this value, the transmit and receive window sizes become invalid. Use set station to change the receive-window and transmit-window sizes. Valid window sizes for mod 8 are 0 to 7; valid window sizes for mod 128 are 8 to 127.
At connection start-up, a SNRME (rather than a SNRM) and extended SDLC frame headers are used.
Example:set link modulo 8
link name name
Establishes a name for the link that you are configuring. This parameter is for informational purposes only.
Enter link name: [LINK_0]?
Enter delay between polls [0.2]?
Enter poll retry count (0=forever) [10]?
Example: set link poll timeout
Enter poll timeout [0.5]?
Configuring the role values so that they are not conducive to each other and to the actual SNA devices in use can prevent successful link activation. Configure the link role as follows:
Specify secondary if the SDLC link is connected to an adjacent SDLC primary device, such as a FEP.
Specify negotiable if a T2.1 (APPN) device is attached and you anticipate XID3 exchange.
It is not required that the respective T2.1 devices perform true end-to-end role negotiation when you configure the router's link as negotiable; the router senses the actual role, whether predetermined or not, and adjusts accordingly. Conversely, if you anticipate end-to-end T2.1 role negotiation and do not configure the router's link role as negotiable, the value you configure influences the role negotiation.
Example: set link role primary
link rts-hold
Sets the time to hold RTS (Request to Send) high after transmitting a frame. This setting is for half-duplex mode and has no effect in full-duplex mode.
Enter RTS hold duration after transmit complete [0.0]?
Example: set link snrm timeout
Enter SNRM response timeout [2.0]?
Enter SNRM retry count (0=forever)[6]?
Internal Clock Speed [0]?
Example: set link type multipoint
link xid/test timeout
Sets the maximum amount of time to wait for an XID or TEST frame response before retransmitting the XID or TEST frame. Applies only to primary stations.
Enter XID and TEST frame response timeout [2.0]?
Enter XID and TEST retry count (0 = forever) [4]?
Example: set station c1 address
Enter station address (in hex) [C1]? ce
Example: set station c1 group-inclusion yes
station address or name max-packet
The maximum size of the packet that the station can receive. The default is 2048 bytes.
Do not set the maximum packet size larger than the link frame size configured with set link frame-size. If you do, the router automatically resets the max packet size to the link frame size, and issues the following ELS message:
SDLC.054: nt 3 SDLC/0 Stn C4-MaxBTU too large for Link adjusted (4096->2048)
set station c1 max-packet
Enter max packet size [2048]?
Enter station name [SDLC_C1]?
Example: set station c1 receive-window
Enter receive window [7]?
Example: set station c1 node-type pu2
station address or name transmit-window
The maximum number of frames the router can transmit before receiving a response frame. The range is 1 to 7. The default is 7.
Example: set station c1 transmit-window
Enter transmit window [7]?
Disable the link station before using this command.
Note: This command does not apply to adjacent primary link stations, that is, when the local router link is defined as secondary.
Syntax: test station name or address #frames frame-size Example:test station c1
Number of frames to send [1]? 5
Frame length [265]?
Starting echo test -- press any key to abort
5 frames sent, 5 frames received, 0 compare errors, 0 timeouts
|
Number of frames
| Number of TEST frames to send. |
|
Frame length
| Length of the frame sent. Do not enter a length larger than the maximum frame length of the specified station. |
Exit [C] [M]
Use the exit command to return to the previous prompt.
exit