R2511-HP MSR Router Series Layer 2 - WAN Command Reference(V5)

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Usage guidelines
SDLC is an "unbalanced" link layer protocol. The end systems across 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.
In the SDLC role configuration, 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.
Examples
# Set the role of the SDLC device connected with Serial 2/0 to primary, and the role of the local interface
to secondary.
<Sysname> system-view
[Sysname] interface serial 2/0
[Sysname-Serial2/0] sdlc status secondary
sdlc timer ack
Use sdlc timer ack to configure the primary-station acknowledgment waiting time, the amount of time the
primary SDLC station waits for an acknowledgment from the secondary station after sending an
information frame.
Use undo sdlc timer ack to restore the default.
Syntax
sdlc timer ack mseconds
undo sdlc timer ack
Default
The primary-station acknowledgment waiting time is 3000 milliseconds.
Views
Synchronous serial interface view
Default command level
2: System level
Parameters
mseconds: Primary-station acknowledgment waiting time in milliseconds. The range is 1 to 60000.
Examples
# Set the primary-station acknowledgment waiting time to 2000 milliseconds on Serial 2/0.
<Sysname> system-view
[Sysname] interface serial 2/0
[Sysname-Serial2/0] sdlc timer ack 2000