Configuring Authentication Passwords; Setting The Overload Bit - Dell C9000 Series Networking Configuration Manual

Configuring Authentication Passwords

You can assign an authentication password for routers in Level 1 and for routers in Level 2.
Because Level 1 and Level 2 routers do not communicate with each other, you can assign different passwords
for Level 1 routers and for Level 2 routers. However, if you want the routers in the level to communicate with
each other, configure them with the same password.
To configure a simple text password, use the following commands.
• Configure authentication password for an area.
ROUTER ISIS mode
area-password [hmac-md5] password
Dell supports HMAC-MD5 authentication.
This password is inserted in Level 1 LSPs, Complete SNPs, and Partial SNPs.
• Set the authentication password for a routing domain.
ROUTER ISIS mode
domain-password [encryption-type | hmac-md5] password
Dell supports both DES and HMAC-MD5 authentication methods.
This password is inserted in Level 2 LSPs, Complete SNPs, and Partial SNPs.
To view the passwords, use the show config command in ROUTER ISIS mode or the show running-
config isis command in EXEC Privilege mode.
To remove a password, use either the no area-password or no domain-password commands in ROUTER
ISIS mode.

Setting the Overload Bit

Another use for the overload bit is to prevent other routers from using this router as an intermediate hop in
their shortest path first (SPF) calculations. For example, if the IS-IS routing database is out of memory and
cannot accept new LSPs, the system sets the overload bit and IS-IS traffic continues to transit the system.
To set or remove the overload bit manually, use the following commands.
• Set the overload bit in LSPs.
ROUTER ISIS mode
set-overload-bit
This setting prevents other routers from using it as an intermediate hop in their shortest path first (SPF)
calculations.
• Remove the overload bit.
ROUTER ISIS mode
no set-overload-bit
Intermediate System to Intermediate System 601