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Home Documentation Junos OS Junos CLI Reference CLI Reference M

Junos CLI Reference

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Junos CLI Reference
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{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
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max-lsp-size

date_range 05-Dec-24
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Syntax

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max-lsp-size size;

Hierarchy Level

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[edit logical-systems logical-system-name protocols isis],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols isis],
[edit protocols isis],
[edit routing-instances routing-instance-name protocols isis]
[edit logical-systems logical-system-name protocols isis level],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols isis level]

Description

Modify the maximum size of IS-IS link-state PDUs. IS-IS sends link-state PDUs out of IS-IS enabled interfaces to distribute routing information between the IS-IS nodes. You can configure the maximum lsp size per level or at the global level. If configured at both global and per level, the per level setting takes precedence.

Note:

Set the max lsp size to a value less than or equal to the MTU of all the interfaces within the ISIS domain. Otherwise the bigger size LSP will not get flooded to all the nodes in the domain, which might lead to traffic loss and unforeseen events.

Junos uses ethertype ox8870 to send IS-IS packets with maximum LSP size greater than 1500 bytes, which is not standardized across networks. This can sometimes cause packet loss in networks that do not recognize this value leading to network issues. Therefore, we recommend that you exercise caution when you configure this value to greater than 1500 bytes.

Options

size

Maximum size allocated for IS-IS link-state PDUs.

  • Range: 512 through 9192 bytes

  • Default: 1492 bytes

Required Privilege Level

routing—To view this statement in the configuration.

routing-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 12.1.

Per Level statement introduced in Junos OS Release 23.1

Related Documentation

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