Asterisk is missing the required (TLS) SIP Transport

Updated: 2026-10-01 08:07:13

Symptoms

A critical message saying "Missing required (TLS) SIP Transport" shows up in the logbook, which can be seen in the CoCoS Management.

Details

See screenshot below for an example of the message. The fields "service info" and "developer info" provides more information about the issue.

Log output

Missing required (TLS) SIP Transport

Missing the required SIP Transport 'transport-tls'.

The connector tried to automatically fix this issue but was unable to. OR The transport was not configured or configurations contain invalid characters.

Cause

When the Asterisk Connector starts, it checks whether the required SIP transports are available:

UDP
TLS (secure transport)

These transports are needed so SIP calls can be established correctly.

Since TLS is the standard (recommended) transport, the connector expects the TLS transport to be properly configured.

If the required TLS certificate files are missing or invalid:

The TLS transport cannot start
As a result, the connector reports that the required transport is not available

In short: No valid TLS certificates -> TLS transport fails -> Connector cannot use secure SIP

Solution / Resolution / How To

Fix: no TLS certificate files

1. Connect to the system Connect to the server via SSH ( or any other method ). For this use a tool like: PuTTY SSH
2. Upload the certificate script Upload the script to the `ensure-asterisk-cert.sh` server. This script is included in the CoCoS installation files It is also available on GitHub: https://github.com/Concera-Software/CoCoS-Connector-Asterisk/blob/main/tools/asterisk-installer/src/scripts/ensure-asterisk-cert.sh
3. Run the script Make the script executable and run it: `chmod +x ./ensure-asterisk-cert.sh ./ensure-asterisk-cert.sh`
4. Ensure Asterisk uses the new TLS certificate files 4.1. Copy the values from the script output After running the script, note the following fields: `cert_file` `priv_key_file` `ca_list_file` 4.2. Open the Asterisk configuration file `nano /etc/asterisk/pjsip.conf` (You can also use `vim` or another editor if preferred.) 4.3. Update the TLS transport settings ( when needed ) Locate the `transport-tls` section in the file. Check the following settings: `cert_file` `priv_key_file` `ca_list_file` If the values do not match the script output: Replace them with the values generated by the script.
5. Restart Asterisk using the following command: `systemctl restart asterisk`
6. Verify TLS transport is active Requires root or sudo privileges 6.1. Connect to the remote Asterisk CLI: `/usr/sbin/asterisk -r` 6.1. Run the following CLI command to list active SIP transports. You should be able to see `transport-tls` in this list. `pjsip show transports` You should be able to see `transport-tls` in this list. 6.2. Use `Ctrl+C` or run `exit` to exit the remote CLI.