Administrator Guide
Intermediate System to Intermediate System
(IS-IS)
The intermediate system to intermediate system (IS-IS) is an interior gateway protocol that uses a shortest-path-first algorithm.
IS-IS facilitates the communication between open systems, supporting routers passing both IP and OSI traffic.
A router is considered 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 Networking OS Configuration Guide.
NOTE: The fundamental mechanisms of IS-IS are the same between IPv4 and IPv6. Where there are differences between
the two versions, they are identified and clarified in this chapter. Except where identified, the information in this chapter
applies to both protocol versions.
Topics:
• adjacency-check
• advertise
• area-password
• clear isis
• clns host
• debug isis
• debug isis adj-packets
• debug isis graceful-restart
• 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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808 Intermediate System to Intermediate System (IS-IS)