White Papers

Intermediate System to Intermediate System
(IS-IS)
IS-IS is an interior gateway protocol that uses shortest-path-first algorithm. IS-IS facilitates the communication between open
systems, supporting routers passing through both IP and OSI traffic.
A router is considered as an intermediate system. Networks are partitioned into manageable routing domains called areas.
Intermediate systems send, receive, and forward packets to other routers within their area (Level 1 and Level 1-2 devices). Only
Level 1-2 and Level 2 devices communicate with other areas.
IS-IS protocol standards are listed in the Standard Compliance chapter in the Dell EMC Networking OS Configuration Guide.
NOTE: The fundamental mechanisms of IS-IS are the same for IPv4 and IPv6. However some command modes might vary
when applied to IPV4 and IPV6. These variations have been explicitly explained for such commands. If the variation is not
mentioned, then the information applies to both the protocol versions.
Topics:
• adjacency-check
• advertise
• area-password
• clear config
• clear isis
• clns host
• debug isis
• debug isis adj-packets
• debug isis local-updates
• debug isis snp-packets
• debug isis spf-triggers
• debug isis update-packets
• default-information originate
• description
• distance
• distribute-list in
• distribute-list out
• distribute-list redistributed-override
• domain-password
• graceful-restart ietf
• graceful-restart interval
• graceful-restart restart-wait
• graceful-restart t1
• graceful-restart t2
• graceful-restart t3
• hello padding
• hostname dynamic
• ignore-lsp-errors
• ip router isis
• ipv6 router isis
• isis circuit-type
• isis csnp-interval
• isis hello-interval
• isis hello-multiplier
• isis hello padding
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806 Intermediate System to Intermediate System (IS-IS)