The ipv6 import-route limit command restricts the number of IPv6 routes imported form other routing protocols in the IS-IS view.
The undo ipv6 import-route limit command cancels the restriction.
By default, IS-IS can import IPv6 routes of other routing protocols with no limitation.
ipv6 import-route limit limit-number [ threshold-alarm upper-limit upper-limit-value lower-limit lower-limit-value ] { level-1 | level-2 | level-1-2 }
undo ipv6 import-route limit [ limit-number ] [ threshold-alarm upper-limit upper-limit-value lower-limit lower-limit-value ] { level-1 | level-2 | level-1-2 }
| Parameter | Description | Value |
|---|---|---|
| limit-number | Specifies the maximum number of external IPv6 routes allowed to be imported to an IS-IS area. |
The value is an integer ranging from 1 to 10000000. |
| threshold-alarm | Specifies the alarm threshold for imported IPv6 routes. |
- |
| upper-limit upper-limit-value | Indicates the upper limit that triggers an alarm. If the proportion of the number of imported IPv6 external routes in the maximum number of IPv6 routes exceeds upper-limit-value, an alarm is generated. |
The value is an integer ranging from 1 to 100. The default value is 80. |
| lower-limit lower-limit-value | Indicates the lower limit that triggers a clear alarm. If the proportion of the number of imported IPv6 external routes in the maximum number of IPv6 routes falls below lower-limit-value, a clear alarm is generated. |
The value is an integer ranging from 1 to 100. The default value is 70. |
| level-1 | Specifies the maximum number of external IPv6 routes allowed to be imported to an IS-IS Level-1 area. |
- |
| level-2 | Specifies the maximum number of external IPv6 routes allowed to be imported to an IS-IS Level-2 area. |
- |
| level-1-2 | Specifies the maximum number of external IPv6 routes allowed to be imported to both Level-1 and Level-2. |
- |
Usage Scenario
To implement the communication between an IS-IS routing domain and other routing protocol domains or other IS-IS domains, you can run the ipv6 import-route command to import external IPv6 routes to IS-IS. Importing routes may cause a problem. If the routing table capacity of an IS-IS device is small, importing a large number of external routes may cause the router to reset because the number of routes exceeds the capacity. Therefore, you need to run the ipv6 import-route limit command to restrict the number of imported IPv6 routes to prevent the unexpected router restart.
Prerequisites
You have run the isis command to create an IS-IS process and run the ipv6 enable command to enable IPv6 in the IS-IS process.
Precautions
The value of upper-limit-value must be greater than or equal to the value of lower-limit-value.
# Set the maximum number of external IPv6 routes allowed to be imported to the IS-IS Level-1 area to 100 with the upper limit 85 and lower limit 75.
<sysname> system-view [sysname] isis [sysname-isis-1] ipv6 enable [sysname-isis-1] ipv6 import-route limit 100 threshold-alarm upper-limit 85 lower-limit 75 level-1