• After running upgrade command completed successfully (Documentation: Chapter 11. Upgrading the overcloud) from 16.2 to 17.1.6
• instances (network), routers, and network are unstable.
  a lot of instances and routers are missing comunication with network.
• We can see cpu high utilization in logs:
• 2025-10-09T04:36:20.132Z|00805|poll_loop|INFO|wakeup due to [POLLIN] on fd 23 (10.20.10.101:44630<->10.20.10.101:6642) at lib/stream-fd.c:157 (101% CPU usage)
•  

Device Info (please complete the following information):

• [redhat-release] Red Hat Enterprise Linux release 8.4 (Ootpa)
  [rhosp-release] Red Hat OpenStack Platform release 17.1.6 (Wallaby)

Bug impact

• Network instability

Known workaround

• kcs 7077367 seems similar, but we don't apply it so far, because the bz seems solved on openstack-neutron-18.6.1-17.1.20240918120815.85ff760.el9ost and they have openstack-neutron-18.6.1-17.1.20250408181013.85ff760.el9ost.noarch inside the container

Additional context

• sosreport on case 04275944