Secure Connect Gateway: Upgrade fails after bridge network MTU change

MTU of sae-srs-bridge is changed due to network restriction, per Secure Connect Gateway Virtual Edition (Virtual Appliance/SCG-VE): Unable to register Secure Connect Gateway due to default MTU size not allowed by Internet provider to connect to the Dell Enterprise servers.

After performing version update, the User Interface of the Secure Connect Gateway is unavailable:

docker container ls -all

Reports only the saede-app container:

# docker container ls --all
CONTAINER ID   IMAGE        COMMAND                  CREATED         STATUS          PORTS                                                                          NAMES
0f6a3732c9ef   sae:latest   "/usr/lib/systemd/sy…"   15 months ago   Up 48 seconds   0.0.0.0:162->162/tcp, 0.0.0.0:5700-5704->5700-5704/tcp, 0.0.0.0:162->162/udp   saede-app

journalctl -u srs.docker.service

Shows the following:

# journalctl -u srs.docker.service
-- Logs begin at Wed 2024-01-31 15:46:57 UTC, end at Wed 2024-01-31 15:53:37 UTC. --
Jan 31 15:50:24 e2ecntscgvmwlab01 systemd[1]: Starting SRS Container Service...
Jan 31 15:50:25 e2ecntscgvmwlab01 docker-compose[3615]: The Compose file './cfg.yml' is invalid because:
Jan 31 15:50:25 e2ecntscgvmwlab01 docker-compose[3615]: networks.main_net.ipam.config.subnet is invalid: should use the CIDR format
Jan 31 15:50:25 e2ecntscgvmwlab01 docker-compose[3632]: The Compose file './cfg.yml' is invalid because:
Jan 31 15:50:25 e2ecntscgvmwlab01 docker-compose[3632]: networks.main_net.ipam.config.subnet is invalid: should use the CIDR format
Jan 31 15:50:25 e2ecntscgvmwlab01 docker-compose[3636]: Network "sae-srs-bridge" needs to be recreated - option "com.docker.network.driver.mtu" has changed
Jan 31 15:50:26 e2ecntscgvmwlab01 systemd[1]: srs.docker.service: Main process exited, code=exited, status=1/FAILURE
Jan 31 15:52:35 e2ecntscgvmwlab01 systemd[1]: srs.docker.service: Start-post operation timed out. Stopping.
Jan 31 15:52:35 e2ecntscgvmwlab01 systemd[1]: Failed to start SRS Container Service.
Jan 31 15:52:35 e2ecntscgvmwlab01 systemd[1]: srs.docker.service: Unit entered failed state.
Jan 31 15:52:35 e2ecntscgvmwlab01 systemd[1]: srs.docker.service: Failed with result 'timeout'.

Network sae-srs-bridge is re-created during update, its MTU is reverted to the original value (1500), the previously connected containers refuse to power on.

1. Revert to a snapshot before the upgrade, can be before or after MTU change.
2. Download the upgrade only, DO NOT install.
3. Run the following command:

   1. zypper refresh
      

   2. zypper --non-interactive up container-orchestration
      

4. Modify the below file, insert the highlighted line, make sure the MTU matches the one currently being used.

   # vi /opt/esrsve/container-orchestration/cfg.yml

   networks:
       main_net:
           name: sae-srs-bridge
           driver: bridge
           driver_opts:
               com.docker.network.bridge.name: sae-srs-bridge
               com.docker.network.driver.mtu: 1454
           enable_ipv6: true
           ipam:
               driver: default
               config:
                   - subnet: ${BridgeSubnet}
                   - subnet: fd00:d311:e3c:5c6::/64
   

5. Start saede-app container

   docker start saede-app

6. Wait for the user interface to recover (5-10 minutes) and perform upgrade.