---
name: "traffic_via"
section: "1"
platform: "linux"
package: "trafficserver"
version: "9.2.5+ds-0+deb12u4"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/traffic_via"
---

# traffic\_via(1)

Traffic Server Via header decoder

## NAME

traffic\_via - Traffic Server Via header decoder

## SYNOPSIS

**traffic\_via** \[OPTIONS\] \[VIA ...\]

## DESCRIPTION

**traffic\_via** decodes the Traffic Server Via header codes. Via header strings are passed as command-line options. The enclosing square brackets are optional.

If the argument is '-', **traffic\_via** will filter standard input for Via headers. This modes supports only supports Via headers that are enclosed by square brackets.

## OPTIONS

- **-h, --help**

  Print usage information and exit.

- **-V, --version**

  Print version.

## EXAMPLES

Decode the Via header from command-line arguments:

```
$ traffic_via "[uScMsEf p eC:t cCMp sF]"
Via header is [uScMsEf p eC:t cCMp sF], Length is 22
Via Header Details:
Request headers received from client                   :simple request (not conditional)
Result of Traffic Server cache lookup for URL          :miss (a cache "MISS")
Response information received from origin server       :error in response
Result of document write-to-cache:                     :no cache write performed
Proxy operation result                                 :unknown
Error codes (if any)                                   :connection to server failed
Tunnel info                                            :no tunneling
Cache Type                                             :cache
Cache Lookup Result                                    :cache miss (url not in cache)
Parent proxy connection status                         :no parent proxy or unknown
Origin server connection status                        :connection open failed
```

Decode the Via header from a curl request, using the *X-Debug* plugin:

```
$ curl -H  "X-Debug: Via" -I http://test.example.com | traffic_via -
Via header is uScMsSf pSeN:t cCMi p sS, Length is 24
Via Header Details:
Request headers received from client                   :simple request (not conditional)
Result of Traffic Server cache lookup for URL          :miss (a cache "MISS")
Response information received from origin server       :connection opened successfully
Result of document write-to-cache:                     :no cache write performed
Proxy operation result                                 :served or connection opened successfully
Error codes (if any)                                   :no error
Tunnel info                                            :no tunneling
Cache Type                                             :cache
Cache Lookup Result                                    :cache miss (url not in cache)
Parent proxy connection status                         :no parent proxy or unknown
Origin server connection status                        :connection opened successfully
```

## COPYRIGHT

2026, dev@trafficserver.apache.org