Bug ID 421611: SIP messages through the SIP-ALG may be hairpinned when the destination address is not inside the NAT

Last Modified: Mar 12, 2019

Bug Tracker

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

Known Affected Versions:
11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9, 11.5.2, 11.5.2 HF1, 11.5.3, 11.5.3 HF1, 11.5.3 HF2, 11.5.4, 11.5.4 HF1, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9

Fixed In:
11.6.0

Opened: May 21, 2013
Severity: 2-Critical
Related AskF5 Article:
K15993

Symptoms

SIP messages are sent directly to the peer and not to the SIP-Proxy when both peers are inside the NAT.

Impact

Some SIP messages may not be seen by the SIP-Proxy and cause missed messages and accounting gaps.

Conditions

-- CGNAT and SIP-ALG are configured. -- Peer1 and Peer2 are in the NAT'd network (subscribers). -- SIP-Proxy is located outside the NAT network (internet).

Workaround

None

Fix Information

SIP messages through the SIP-ALG are no longer hairpinned when the destination address is not inside the NAT.

Behavior Change