195
To do…
Use the command…
Remarks
Step 4
Specify the LSP
retransmission interval
on a P2P link
isis timer retransmit
seconds
Optional
5 seconds by default
If a large number of IS-IS interfaces or routes exist, you must specify a proper LSP sending interval to avoid
LSP storms.
Specifying LSP lengths
IS-IS messages cannot be fragmented at the IP layer because they are directly encapsulated in
frames. Therefore, IS-IS routers in an area must send LSPs smaller than the smallest interface MTU
in this area.
If the IS-IS routers have different interface MTUs, H3C 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 do…
Use the command…
Remarks
Step 1
Enter system view
system-view
––
Step 2
Enter IS-IS view
isis
[
process-id
] [
vpn-instance
vpn-
instance-name
]
––
Step 3
Specify the maximum length
of generated Level-1 LSPs or
Level-2 LSPs
lsp-length originate
size
[
level-1
|
level-2
]
1497 bytes by default
Step 4
Specify the maximum length
of received LSPs
lsp-length receive
size
1497 bytes by default
Enabling LSP flash flooding
Changed LSPs may trigger SPF recalculation, so you can enable LSP flash flooding to advertise
the changed LSPs before the router recalculates routes. Doing so can speed up network
convergence.
To do…
Use the command…
Remarks
Step 1
Enter system
view
system-view
––
Step 2
Enter IS-IS view
isis
[
process-id
] [
vpn-instance
vpn-instance-name
]
––