Example of Viewing the Overload Bit Setting
When the bit is set, a 1 is placed in the OL column in the show isis database command output. The
overload bit is set in both the Level-1 and Level-2 database because the IS type for the router is
Level-1-2.
Dell#show isis database
IS-IS Level-1 Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/
OL
B233.00-00 0x00000003 0x07BF 1074 0/0/0
eljefe.00-00 * 0x0000000A 0xF963 1196 0/0/1
eljefe.01-00 * 0x00000001 0x68DF 1108 0/0/0
eljefe.02-00 * 0x00000001 0x2E7F 1099 0/0/0
Force10.00-00 0x00000002 0xD1A7 1088 0/0/0
IS-IS Level-2 Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/
OL
B233.00-00 0x00000006 0xC38A 1110 0/0/0
eljefe.00-00 * 0x0000000E 0x53BF 1196 0/0/1
eljefe.01-00 * 0x00000001 0x68DF 1108 0/0/0
eljefe.02-00 * 0x00000001 0x2E7F 1099 0/0/0
Force10.00-00 0x00000004 0xCDA9 1093 0/0/0
Dell#
Debugging IS-IS
To debug IS-IS processes, use the following commands.
• View all IS-IS information.
EXEC Privilege mode
debug isis
• View information on all adjacency-related activity (for example, hello packets that are sent and
received).
EXEC Privilege mode
debug isis adj-packets [interface]
To view specific information, enter the following optional parameter:
– interface: Enter the type of interface and slot/port information to view IS-IS information on that
interface only.
• View information about IS-IS local update packets.
EXEC Privilege mode
debug isis local-updates [interface]
To view specific information, enter the following optional parameter:
– interface: Enter the type of interface and slot/port information to view IS-IS information on that
interface only.
• View IS-IS SNP packets, include CSNPs and PSNPs.
EXEC Privilege mode
debug isis snp-packets [interface]
To view specific information, enter the following optional parameter:
Intermediate System to Intermediate System
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