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clear isis database


Syntax (EX Series Switches and QFX Series)


Remove the entries from the IS-IS link-state database, which contains prefixes and topology information.


You can also use the purge command with any of the options to discard rather than delete the specified LSA entries. This command is useful only for testing. Use it with care, because it causes significant network disruption.



Remove all entries from the IS-IS link-state database for all routing instances.


(Optional) Name of the database entry.

instance instance-name

(Optional) Clear all entries for the specified routing instance.

logical-system (all | logical-system-name)

(Optional) Perform this operation on all logical systems or on a particular logical system.


(Optional) Discard all entries in the link-state advertisement database. All link-state advertisements are set to MAXAGE and are flooded. The database is repopulated when the originators of the link-state advertisements receive the MAXAGE link-state advertisements and reissue them.

Required Privilege Level


Output Fields

See show isis database for an explanation of output fields.

Sample Output

clear isis database

The following sample output displays IS-IS link-state database information before and after the clear isis database all command is entered:

Release Information

Command introduced before Junos OS Release 7.4.

purge option (and all options that are dependent on the purge option) hidden in Junos OS Release 13.3R2.