Configuring SDLC roles
In contrast with HDLC, SDLC is an "unbalanced" link layer protocol. The ends of a TCP connection are not equal in the positions: one is primary and the other is secondary. The primary station, whose role is primary, plays a dominant role and controls the whole connection process. The secondary station, whose role is secondary, is controlled by the primary station. You must configure a role for an SDLC interface.
The role of an interface should be determined by the role of the SDLC device to which this router is connected:
If the SDLC device connected with the local router has a role of primary, the local interface should be configured to have a role of secondary.
If the SDLC device connected with the local router has a role of secondary, the local interface should be configured to have a role of primary.
An IBM mainframe has a role of primary, and a terminal device such as a UNIX host or an ATM has a role of secondary.
To configure an SDLC role:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. Configure an SDLC role. | sdlc status { primary | secondary } | By default, no SDLC role is configured. |