| The web interface does not open |
Check the logs: journalctl -u opennccm -n 100 and sudo nginx -t. Check the firewall (port 443). |
| “Could not open syslog UDP/514” in the log |
Another service is using the port (e.g. rsyslog with UDP reception enabled). Disable that reception or change NCM_SYSLOG_PORT in /etc/opennccm/opennccm.env. |
| Backup: “TCP connection to device failed” or timeout |
No connectivity or SSH is closed. Try ssh from the server; check the device’s VTY ACLs. |
| Old device: “no matching host key type found. Their offer: ssh-rsa” or “Incompatible ssh peer” |
The device (e.g. Ubiquiti EdgeSwitch, Cisco IOS 12.x, old HP ProCurve) only supports SHA-1 algorithms. Since version 1.3.1 OpenNCCM accepts them automatically only as a last resort, so upgrade with sudo opennccm update. Modern devices keep using modern algorithms. In the long run, upgrading the device firmware is advisable. |
| “The device asks for a password for privileged mode (enable)…” or “Failed to enter enable mode” |
The device requires an enable password different from the login one (OpenNCCM already tries with no password and with the login one). Enter it in Credentials → Enable / secret of the credential assigned to the device and back up again. |
| The web “Update” button shows “fatal: $HOME not set” |
Bug in version 1.6.0/1.6.1, fixed in 1.6.2. Upgrade once from the console with sudo opennccm update; from then on the button works. |
| The browser does not offer to save the user name and password |
The site has a certificate warning. Install the “OpenNCCM CA” authority on the PC (see HTTPS and firewall) and always use the same address. |
| I lost the phone with two-step verification |
Another administrator removes it in Users → Edit, or on the server: sudo opennccm reset-2fa USER. |
| “The account is temporarily locked” |
5 wrong passwords in a row: wait 15 minutes or ask an administrator to set a new password (that unlocks it). |
| The web SSH console disconnects when opened |
It only works with devices reached over SSH and for users who have permission (Settings → Security and access). Behind another proxy, that proxy must allow WebSocket. |
| Backup: “Authentication failed” |
Wrong user/password in the assigned credential. |
| Backup: “Pattern not detected” |
The prompt or privileged mode is not the expected one: the enable password is missing, or the device_type does not match the device. |
| Backup: “invalid output” |
The backup command does not exist in that version. Set a custom backup command on the device. |
| Changes are not detected in real time |
The device does not send syslog, sends it from another IP, or a firewall blocks UDP 514. Check with sudo tcpdump -ni any udp port 514. |
| Telnet “not supported” |
That platform has no Telnet variant in Netmiko: use SSH. |
| Forgot the password or cannot sign in |
sudo opennccm users to list users and sudo opennccm reset-password USER 'NewPassword123'. After 10 failed attempts sign-in is blocked for 15 minutes: sudo opennccm restart unblocks it. |
| Firmware: “MD5 not verified” |
Damaged image or not enough space; on Cisco enable ip scp server enable. |
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