# VMs Inaccessible due to Underlying Hypervisors Frequently Going Offline ## Problem The VMs are inaccessible via SSH and console as the Hypervisor connectivity is flapping frequently. ```bash $ ssh ubuntu@ Connection closed by [VM_IP] port 22 ``` ## Environment * Private Cloud Director Virtualization - till v2025.4-497 * Self-Hosted Private Cloud Director Virtualization - till v2025.4-497 * Component - Networking ## Cause * When the DHCP lease expires, the host interface gets reconfigured. During this process, interfaces that are attached to the bridge also receive IP addresses unexpectedly. Because of this, `ovn-controller` enters a failed state while processing its configuration updates. * This is a known issue and is reported internally with ID: **PCD-2492.** ## Diagnostics {% code title="neutron logs:" %} ```ruby pf9_app.py ERROR - pf9-neutron-ovn-controller:get_config failed: b'' Command: sudo ip route add default via [IP] dev br-phy1 metric 0 failed. 2:b'RTNETLINK answers: File exists\\n' session.py ERROR - Bad message, app config or reading current app config. Message : {'opcode': 'heartbeat'} Traceback (most recent call last): File "_opt_pf9_hostagent_lib_python3.9_site-packages_bbslave_session.py", line 625, in handle_msg current_config = get_current_config() File "_opt_pf9_hostagent_lib_python3.9_site-packages_bbslave_session.py", line 262, in get_current_config config = app_db.get_current_config() File "_opt_pf9_hostagent_lib_python3.9_site-packages_pf9app_app_db.py", line 80, in get_current_config 'config': app.get_config(), File "_opt_pf9_hostagent_lib_python3.9_site-packages_pf9app_pf9_app.py", line 311, in get_config raise ConfigOperationError() pf9app.exceptions.ConfigOperationError ``` {% endcode %} Network related files: ```bash $ ls -lt /run/systemd/network/ -rw-r----- 1 root systemd-network 213 Jun 11 06:25 10-netplan-bond0.600.network -rw-r----- 1 root systemd-network 63 Jun 11 06:25 10-netplan-bond0.601.netdev -rw-r----- 1 root systemd-network 130 Jun 11 06:25 10-netplan-bond0.601.network -rw-r----- 1 root systemd-network 63 Jun 11 06:25 10-netplan-bond0.602.netdev -rw-r----- 1 root systemd-network 131 Jun 11 06:25 10-netplan-bond0.602.network -rw-r----- 1 root systemd-network 65 Jun 11 06:25 10-netplan-bond0.3001.netdev -rw-r----- 1 root systemd-network 155 Jun 11 06:25 10-netplan-bond0.3001.network -rw-r----- 1 root systemd-network 63 Jun 11 06:25 10-netplan-bond0.600.netdev -rw-r----- 1 root systemd-network 196 Jun 11 06:25 10-netplan-bond0.netdev -rw-r----- 1 root systemd-network 195 Jun 11 06:25 10-netplan-bond0.network -rw-r----- 1 root root 82 Jun 11 06:25 10-netplan-enp1s0f0.link -rw-r----- 1 root systemd-network 134 Jun 11 06:25 10-netplan-enp1s0f0.network -rw-r----- 1 root root 82 Jun 11 06:25 10-netplan-enp1s0f1.link -rw-r----- 1 root systemd-network 134 Jun 11 06:25 10-netplan-enp1s0f1.network ``` {% code title="/var/log/pf9/hostagent.log" %} ```ruby pf9_app.py ERROR - pf9-neutron-ovn-controller:get_config failed: b'' Command: sudo ip route add default via dev br-phy12 metric 0 failed. 2:b'RTNETLINK answers: File exists\\n' session.py ERROR - Bad message, app config or reading current app config. Message : {'opcode': 'heartbeat'} Traceback (most recent call last): File "_opt_pf9_hostagent_lib_python3.9_site-packages_bbslave_session.py", line 625, in handle_msg current_config = get_current_config() File "_opt_pf9_hostagent_lib_python3.9_site-packages_bbslave_session.py", line 262, in get_current_config config = app_db.get_current_config() File "_opt_pf9_hostagent_lib_python3.9_site-packages_pf9app_app_db.py", line 80, in get_current_config 'config': app.get_config(), File "_opt_pf9_hostagent_lib_python3.9_site-packages_pf9app_pf9_app.py", line 311, in get_config raise ConfigOperationError() pf9app.exceptions.ConfigOperationError ``` {% endcode %} ## Resolution The fix for the bug is available in the v2025.6 and above releases. ## Workaround Check if the interface IP is assigned to the bridge and the default route is associated with the bridge. * If yes, delete the default route via *bondx.x*. * If not, reboot the host and check again. ```ruby $ ip r default via [VM_IP] dev br-phy12 default via [VM_IP] dev bond0.10 proto static 1.1.1.1_24 dev br-phy12 proto kernel scope link src 1.1.1.251 1.1.1.2_24 dev bond0.10 proto kernel scope link src 1.1.1.251 1.1.1.3_24 dev br-phy15 proto kernel scope link src 1.1.1.251 1.1.1.4_24 dev bond0.50 proto kernel scope link src 1.1.1.251 $ sudo ip route del default via dev bond0.10 ``` ## Additional Information * For further questions/concerns regarding the bug, reach out to the [Platform9 Support Team](https://support.platform9.com/). --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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