OCP 4.14-4.17: remove EgressIP SNAT from gateway router

remove-snat-gw.sh

#!/bin/bash
# Version 1.0 (23 Apr 2025)
# Martin Kennelly (OCP Networking)
# Designed to assist with https://issues.redhat.com/browse/OCPBUGS-42303
# Requires ovn-northd+ovn-controller to sync at least once for SNAT removal changes to propagate to data plane
# Must be executed before ovnkube-controller is started

DATE=$(date +"%Y-%m-%d-%H-%M")
echo "$DATE"
for NAT_UUID in $(ovn-nbctl --bare --column _uuid find nat external-ids:\"name\"!=\"\") ; do \
   GW_Router_NAT_UUID=$(ovn-nbctl --bare --column _uuid,nat find logical_router | grep -B1 "$NAT_UUID" | awk {'print $1'} | head -n1)
   if [[ -n "${GW_Router_NAT_UUID}" ]]; then
      ovn-nbctl remove logical_router "${GW_Router_NAT_UUID}" nat "${NAT_UUID}"
      echo "Removed EgressIP (S)NAT with NAT UUID ${NAT_UUID} from Gateway Logical Router UUID ${GW_Router_NAT_UUID}"
  fi
done