Configuring LSP Parameters

You can configure the transmission interval, retransmission interval, and retransmission throttle interval for LSPs on an interface-specific basis.

isis lsp-interval

Use to configure the delay between successive IS-IS link-state PDU (LSP) transmissions.
You can choose an interval in the range 1–4294967295 milliseconds. For example, setting 100 milliseconds allows 10 packets per second.
The default value is 33 milliseconds.
If your network has many IS-IS neighbors and interfaces, a particular router may have difficulty with the CPU load imposed by LSP transmission and reception. If this is the case, you can reduce the LSP transmission rate by issuing this command.
Examplehost1(config-if)#isis lsp-interval 100
Use the no version to restore the default value, 33 milliseconds.
See isis lsp-interval

isis retransmit-interval

Use to configure the number of seconds between the retransmission of IS-IS LSPs with the same LSP ID for point-to-point links.
You can select an interval in the range 1–65535 seconds.
The default value is 5 seconds.
Specify a number greater than the expected round-trip delay between any two routers on your network.
Always specify conservatively; otherwise, excessive retransmission can result.
Because retransmissions occur only when LSPs are dropped, when you set isis retransmit-interval to a higher value, it has little effect on reconvergence.
Set to a higher value when routers have many neighbors or more paths over which LSPs can be flooded.
Use a large value for serial lines.
Examplehost1(config-if)#isis retransmit-interval 60
Use the no version to restore the default value, 5 seconds.
See isis retransmit-interval

isis retransmit-throttle-interval

Use to configure the maximum rate at which IS-IS LSPs are retransmitted on point-to-point links. The interval is the number of milliseconds between packets.
You can choose an interval in the range 0–65535 milliseconds.
The default delay value is 33 milliseconds.
The isis retransmit-throttle-interval is the maximum rate at which IS-IS LSPs are retransmitted. It is different from isis lsp-interval, which is the rate at which LSPs are transmitted on the interface; and it is different from isis retransmit-interval, which is the period between successive retransmissions of the same LSP. Use all three commands with each other to control the load of routing traffic from one router to its neighbors.
Typically, you can set this interval for very large networks with many LSPs and many interfaces as a way of controlling LSP retransmission traffic.
Example host1(config-if)#isis retransmit-throttle-interval 300
Use the no version to restore the default value, 33 milliseconds.
See isis retransmit-throttle-interval