Last Modified: Sep 18, 2026
Affected Product(s):
BIG-IP LTM
Known Affected Versions:
21.0.0.1, 21.0.0.2, 21.0.0.3
Fixed In:
21.1.0
Opened: Jan 07, 2026 Severity: 2-Critical
TMUI and TMSH were unreachable/ inaccessible, when monitors are configured at scale. SSH connectivity is also impacted due to the same reason.
Access via tmsh, TMUI, and SSH degrades, resulting in BIG-IP system inaccessibility.
When monitors are configured at scale and active probing is enabled, access via tmsh, TMUI, and SSH degrades, resulting in BIG-IP system inaccessibility.
ARP Cache threshold and NF connection tracking configuration values have been fine tuned to reduce the ARP cache flooding and connection tracking limit.
ARP Cache threshold and NF connection tracking configuration values have been fine tuned to reduce the ARP cache flooding and connection tracking limit. ARP cache threshold configs: net.ipv4.neigh.default.gc_thresh1, thresh2, thresh3 net.ipv6.neigh.default.gc_thresh1, thresh2, thresh3 Connection tracking: net.netfilter.nf_conntrack_max