Bug ID 898653: MR::available_for_routing iRule command prevents client side connections from being counted as available for routing towards

Last Modified: Dec 13, 2023

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

Known Affected Versions:
14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,, 15.1.6,, 15.1.7, 15.1.8,,, 15.1.9,, 15.1.10,,, 16.0.0,, 16.0.1,,

Fixed In:

Opened: Apr 14, 2020

Severity: 4-Minor


In systems with a large number of incoming connections from a low number of client IP addresses, the connections are not spread across all TMMs. All entries for a client IP address are stored on the same TMM. Lookup of one of the records returns all records for an IP address. This can lead to exceeding the available bits available for reference counting.


An internal overflow can cause a fault. This might result in a crash or core.


A large number of incoming connections from a low number of client IP addresses.



Fix Information

You can now identify which client side connections do not need to have messages routed towards them using a new MR::available_for_routing iRule command. Note: If reverse routing is not required, there is no need to include the client side connections.

Behavior Change

There is a new MR::available_for_routing iRule command to flag that a connection should not have messages routed towards them.

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips