Bug ID 1291073: Configuring DNS/NAT46 with small subnet will constantly return sorry IP

Last Modified: Apr 28, 2025

Affected Product(s):
BIG_IP_NEXT(SPK) SPK(all modules)

Fixed In:
1.7.2

Opened: Apr 19, 2023

Severity: 3-Major

Symptoms

A small subnet (8 IP addresses for example), will always return a sorry IP

Impact

Client egress traffic will always be directed towards the sorry IP.

Conditions

- Configured F5SPKEgress with a small dnsNat46Ipv4Subnet (eg. 8ips), where the number of (tmm pods * allocated cpus per pod) is less than (subnet ip count / 2).

Workaround

Increase the size of dnsNat46Ipv4Subnet, or reduce the number of total allocated cpus (less pods, or less allocated cpus per pod)

Fix Information

Small subnets now work as expected, as long each cpu can allocate at least 1 IP; a cpu cannot have 0 allocated IPs.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips