HP MSR Series Configuration Manual page 150

If the IS-IS routers have different interface MTUs, HP recommends configuring the maximum size of
generated LSP packets to be smaller than the smallest interface MTU in this area. Otherwise, the routers
must dynamically adjust the LSP packet size to fit the smallest interface MTU, which takes time and affects
other services.
To specify LSP lengths:
Step
1. Enter system view.
2. Enter IS-IS view.
3. Specify the maximum length
of generated Level- 1 LSPs or
Level-2 LSPs.
4. Specify the maximum length
of received LSPs.
Enabling LSP flash flooding
Changed LSPs can trigger SPF recalculation. To advertise the changed LSPs before the router recalculates
routes for faster network convergence, enable LSP flash flooding.
To enable LSP flash flooding:
Step
1. Enter system view.
2. Enter IS-IS view.
3. Enable LSP flash
flooding.
Enabling LSP fragment extension
After LSP fragment extension is enabled for an IS-IS process, the MTUs of all the interfaces running the
IS-IS process must not be less than 512. Otherwise, LSP fragment extension will not take effect.
At least one virtual system must be configured for the router to generate extended LSP fragments. An IS-IS
process allows a maximum of 50 virtual systems.
To enable LSP fragment extension:
Step
1. Enter system view.
2. Enter IS-IS view.
3. Enable LSP fragment
extension and specify the
working mode.
4. Configure a virtual system
ID.
Command
system-view
isis [ process-id ] [ vpn-instance
vpn-instance-name ]
lsp-length originate size [ level-1 | level-2 ]
lsp-length receive size
Command
system-view
isis [ process-id ] [ vpn-instance vpn-instance-name ]
flash-flood [ flood-count flooding-count |
max-timer-interval flooding-interval | [ level-1 |
level-2 ] ] *
Command
system-view
isis [ process-id ] [ vpn-instance
vpn-instance-name ]
lsp-fragments-extend [ [ level-1 | level-1-2 |
level-2 ] | [ mode-1 | mode-2 ] ] *
virtual-system virtual-system-id
138
Remarks
N/A
N/A
1497 bytes by default.
1497 bytes by default.
Remarks
N/A
N/A
Not enabled by
default.
Remarks
N/A
N/A
Not enabled by default.
Not configured by default.