enable isis hello-padding

enable isis [vlan all | {vlan} vlan_name] hello-padding


This command enables the padding of hello PDUs on one or all This command is available on the ExtremeSwitching X440-G2, X450-G2, X460-G2, X465, X590, X620, X670-G2, X690, X695, X870, 5320, 5420, 5520 series switches.s.

Syntax Description

vlan all Enables hello padding on all IS-IS VLANs.
vlan_name Specifies a single VLAN on which hello padding is enabled.



Usage Guidelines

When hello padding is enabled, IS-IS pads hello packets to the interface MTU. This is used among neighbors to verify that adjacencies have the same MTU configured on either end. The disadvantage of hello padding is the price of bandwidth consumed by larger packets.


The following command enables hello padding on the SJvlan VLAN:

enable isis SJvlan hello-padding


This command was first available in ExtremeXOS 12.1.

Platform Availability

This command is available on platforms with a Core or Premier license as described in the ExtremeXOS and Switch Engine 31.7 Feature License Requirements document.