29-63
Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 29 Configuring IP Unicast Routing
Configuring ISO CLNS Routing
Nonstop Forwarding Awareness
The integrated IS-IS NSF Awareness feature is supported for IPv4 in the metro IP access image. The
feature allows customer premises equipment (CPE) routers that are NSF-aware to help NSF-capable
routers perform nonstop forwarding of packets. The local router is not necessarily performing NSF, but
its awareness of NSF allows the integrity and accuracy of the routing database and link-state database
on the neighboring NSF-capable router to be maintained during the switchover process.
This feature is automatically enabled and requires no configuration. For more information on this
feature, see the Integrated IS-IS Nonstop Forwarding (NSF) Awareness Feature Guide at this URL:
http://www.cisco.com/en/US/docs/ios/12_2t/12_2t15/feature/guide/isnsfawa.html
Enabling IS-IS Routing
To enable IS-IS, you specify a name and NET for each routing process. You then enable IS-IS routing
on the interface and specify the area for each instance of the routing process.
Default-information originate
Disabled.
Log IS-IS adjacency state changes.
Disabled.
LSP generation throttling timers
Maximum interval between two consecutive occurrences: 5 seconds.
Initial LSP generation delay: 50 ms.
Hold time between the first and second LSP generation: 5000 ms.
LSP maximum lifetime (without a refresh)
1200 seconds (20 minutes) before t.he LSP packet is deleted.
LSP refresh interval
Send LSP refreshes every 900 seconds (15 minutes).
Maximum LSP packet size
1497 bytes.
NSF
1
Awareness
Enabled
2
. Allows Layer 3 switches to continue forwarding packets from a
neighboring NSF-capable router during hardware or software changes.
Partial route computation (PRC) throttling
timers
Maximum PRC wait interval: 5 seconds.
Initial PRC calculation delay after a topology change: 2000 ms.
Hold time between the first and second PRC calculation: 5000 ms.
Partition avoidance
Disabled.
Password
No area or domain password is defined, and authentication is disabled.
Set-overload-bit
Disabled. When enabled, if no arguments are entered, the overload bit is set
immediately and remains set until you enter the no set-overload-bit command.
Shortest path first (SPF) throttling timers
Maximum interval between consecutive SFPs: 10 seconds.
Initial SFP calculation after a topology change: 5500 ms.
Holdtime between the first and second SFP calculation: 5500 ms.
Summary-address Disabled.
1.
NSF = Nonstop Forwarding
2.
IS-IS NSF awareness is enabled for IPv4 on switches running the metro IP access image.
Table 29-12
Default IS-IS Configuration (continued)
Feature
Default Setting