Configuring The Attached Bit; Configuring The Transient Mode For Hello Padding; Configuring A Summary Address - Cisco Nexus 7000 Series Configuration Manual

Chapter 9 Configuring IS-IS
S e n d d o c u m e n t c o m m e n t s t o n e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m .
Command
set-overload-bit {always | on-startup
{ seconds | wait-for bgp as-number }}
[suppress [interlevel | external]]
Example:
switch(config-router)# set-overload-bit
on-startup 30

Configuring the Attached Bit

You can configure the attached bit to control which Level1/Level2 router that the Level 1 routers use as
the default route to the Level 2 area. If you disable setting the attached bit, the Level 1 routers will not
use this Level1/Level 2 router to reach the Level 2 area.
To configure the attached bit for a Level1/Level2 router, use the following command in router
configuration mode:
Command
[no] attached-bit
Example:
switch(config-router)# no attached-bit

Configuring the Transient Mode for Hello Padding

You can configure the transient mode for hello padding to pad hello packets when IS-IS establishes
adjacency and remove that padding after IS-IS establishes adjacency.
To configure the mode for hello padding, use the following command in router configuration mode:
Command
[no] isis hello-padding
Example:
switch(config-if)# no isis hello-padding

Configuring a Summary Address

You can create aggregate addresses that are represented in the routing table by a summary address. One
summary address can include multiple groups of addresses for a given level. Cisco NX-OS advertises
the smallest metric of all the more-specific routes.
BEFORE YOU BEGIN
Ensure that you have enabled the IS-IS feature (see the
page
Ensure that you are in the correct VDC (or use the switchto vdc command).
OL-20002-02
9-7).
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
Purpose
Sets the overload bit for IS-IS. The seconds range
is from 5 to 86400.
Purpose
Configures the Level1/Level 2 router to set the
attached bit. This is enabled by default.
Purpose
Pads the hello packet to the full MTU. The default
is enabled. Use the no form of this command to
configure the transient mode of hello padding.
"Enabling the IS-IS Feature" section on
Configuring IS-IS
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