Bug ID 625291: dhclient doesn't honor 'interface-mtu' request-options

Last Modified: Jun 04, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP VE(all modules)

Known Affected Versions:
13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5

Fixed In:
13.0.0

Opened: Oct 27, 2016
Severity: 4-Minor

Symptoms

Requesting MTU value from DHCP server is explicitly disabled using a configuration similar to the following: tmsh modify sys management-dhcp sys-mgmt-dhcp-config request-options delete { interface-mtu }. But if DHCP send MTU value in its reply, this MTU will be configured on BIG-IP management interface.

Impact

BIG-IP accepts the MTU value provided.

Conditions

DHCP server ignoring option sent by BIG-IP DHCP client.

Workaround

1. Add supersede interface-mtu 1500; to interface "mgmt" section of the /etc/dhclient.conf file. 2. Restart dhclient.

Fix Information

dhclient now honors 'interface-mtu' request-options.

Behavior Change