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You can configure only one IS-IS routing process to perform Level 2 routing. A level-1-2 designation
performs Level 1 and Level 2 routing at the same time.
Related
Commands
● ip router isis — configures IS-IS routing processes for IP on interfaces and attaches an area
designator to the routing process.
● net — configures an IS-IS network entity title (NET) for a routing process.
● is-type — assigns a type for a given area.
set-overload-bit
To set the overload bit in its non-pseudonode LSPs, configure the router. This setting prevents other routers from using it as an
intermediate hop in their shortest path first (SPF) calculations.
Syntax
set-overload-bit
To return to the default values, use the no set-overload-bit command.
Defaults Not set.
Command Modes
● ROUTER ISIS (for IPv4)
● CONFIGURATION-ROUTER-ISIS-ADDRESS-FAMILY-IPV6 (for IPv6)
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
Set the overload bit when a router experiences problems, such as a memory shortage due to an
incomplete link state database which can result in an incomplete or inaccurate routing table. If you set the
overload bit in its LSPs, other routers ignore the unreliable router in their SPF calculations until the router
has recovered.
show config
Display the changes you made to the IS-IS configuration. Default values are not shown.
Syntax
show config
Command Modes
● ROUTER ISIS (for IPv4)
● CONFIGURATION-ROUTER-ISIS-ADDRESS-FAMILY-IPV6 (for IPv6)
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Example (Router-
Isis)
The bold section identifies that Multi-Topology IS-IS is enabled in Transition mode.
Dell(conf-router_isis)#show config
!
router isis
clns host ISIS 49.0000.0001.F100.E120.0013.00
log-adjacency-changes
net 49.0000.0001.F100.E120.0013.00
!
address-family ipv6 unicast
maximum-paths 16
multi-topology transition
Intermediate System to Intermediate System (IS-IS) 711