diff --git a/fern/advanced/sip/troubleshoot-sip-trunk-credential-errors.mdx b/fern/advanced/sip/troubleshoot-sip-trunk-credential-errors.mdx index fa43fe560..0fbc96965 100644 --- a/fern/advanced/sip/troubleshoot-sip-trunk-credential-errors.mdx +++ b/fern/advanced/sip/troubleshoot-sip-trunk-credential-errors.mdx @@ -36,15 +36,18 @@ This is the most common cause of this error. ### What happens -Vapi's API accepts both hostnames (for example, `sip.example.com`) and IPv4 addresses (for example, `203.0.113.10`) in the `gateways[].ip` field. However, the underlying SBC only accepts IPv4 addresses. When you provide a hostname, the SBC rejects the gateway configuration. +Vapi's API accepts both hostnames (for example, `sip.example.com`) and IPv4 addresses (for example, `203.0.113.10`) in the `gateways[].ip` field. However, **hostnames only work for outbound-only gateways**. For inbound-enabled gateways, the SBC requires a numeric IPv4 address to match the origin of incoming SIP requests. When you provide a hostname for an inbound-enabled gateway, the SBC rejects the gateway configuration. ### How to check -Look at the value you passed in `gateways[].ip`. If it contains letters (for example, `sip.example.com`), it is a hostname. The SBC needs a numeric IPv4 address instead. +Look at the value you passed in `gateways[].ip` and the `inboundEnabled` setting: + +- If `inboundEnabled` is `true` (the default) and `gateways[].ip` contains a hostname (for example, `sip.example.com`), this is the problem. Inbound gateways require a numeric IPv4 address. +- If `inboundEnabled` is `false` (outbound-only), hostnames are accepted and this is not the cause of your error. ### How to fix -Resolve the hostname to its IPv4 address, then use that IP directly. +If your gateway has inbound enabled, resolve the hostname to its IPv4 address, then use that IP directly. @@ -76,7 +79,7 @@ Replace the hostname with the numeric IPv4 address in your gateway configuration "ip": "203.0.113.10", "port": 5060, "outboundEnabled": true, - "inboundEnabled": false + "inboundEnabled": true } ] } @@ -86,8 +89,9 @@ Replace the hostname with the numeric IPv4 address in your gateway configuration - Always use the IPv4 address, not the hostname. If your provider's IP changes, - you need to update the gateway configuration. + Hostnames are supported for outbound-only gateways (`inboundEnabled: false`). + For inbound-enabled gateways, always use a numeric IPv4 address. If your + provider's IP changes, you need to update the gateway configuration. ## Inbound enabled on an outbound-only trunk @@ -157,7 +161,7 @@ The table below lists all available options for each entry in the `gateways` arr | Option | Type | Default | Description | | -------------------- | ------- | --------- | ------------------------------------------------------------------------------ | -| `ip` | string | (required)| IPv4 address of your SIP gateway. Must be a numeric IP address, not a hostname.| +| `ip` | string | (required)| Server address of your SIP gateway. Use a numeric IPv4 address for inbound-enabled gateways. Hostnames are accepted for outbound-only gateways (`inboundEnabled: false`).| | `port` | number | `5060` | SIP signaling port. | | `netmask` | number | `32` | Subnet mask for inbound IP matching. Valid range: 24 to 32. | | `inboundEnabled` | boolean | `true` | Whether this gateway accepts inbound calls. Set to `false` for outbound-only trunks. |