Bug ID 608742: DHCP: DHCP renew ACK messages from server are getting dropped by BIG-IP in Forward mode.

Last Modified: Apr 28, 2025

Affected Product(s):
BIG-IP PEM(all modules)

Known Affected Versions:
11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 11.6.1 HF1, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2

Fixed In:
13.0.0, 12.1.2, 11.6.1 HF2

Opened: Aug 02, 2016

Severity: 3-Major

Related Article: K48561135

Symptoms

When the BIG-IP system is configured in Forwarding mode, the BIG-IP system drops the renewal ACK message from the server in response to unicast renewal message from DHCP clients.

Impact

Unicast DHCP renewal requests are not responded to with ACKs. DHCP clients will send broadcast renewal messages and will receive ACK from servers.

Conditions

-- BIG IP system configured in forwarding mode. -- DHCP clients sending unicast renewal message to DHCP server.

Workaround

None.

Fix Information

After being unable to receive ACK responses from DHCP servers for unicast DHCP renewal messages, the DHCP client will send broadcast DHCP renewal messages and receive an ACK from the DHCP server and ACKs forwarded by the BIG-IP system and received by DHCP clients.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips