Setting the overload bit

The overload bit can be configured so that when an IS is overloaded, other ISs will not use the overloaded IS to forward traffic. The following task specifies that the overload bit is set upon system startup and remains set until BGP has converged and specifies that the device that 240 seconds is the maximum time that IS-IS will wait for BGP convergence to complete.

About this task

Procedure

Enter the configure terminal command to access global configuration mode.
```
device# configure terminal
```
Enter the router isis command to enter IS-IS router configuration mode and enable IS-IS on the device.
```
device(config)# router isis
```
Enter the set-overload-bit command with the on-startup and wait-for-bgp parameters, specifying a value, to configure the device to set the overload bit upon system startup. The overload bit remains set until BGP has converged. 86,400 seconds is the maximum time that IS-IS waits for BGP convergence to complete.
```
device(config-isis-router)# set-overload-bit on-startup wait-for-bgp 86400
```

Example

The following example configures the overload bit on system startup until BGP has converged. The maximum time that the device waits for BGP convergence to complete is 86400 seconds.

device# configure terminal
device(config)# router isis
device(config-isis-router)# set-overload-bit on-startup wait-for-bgp 86400