The XDebug plugin allows HTTP clients to debug the operation of
the Traffic Server cache using the default
X-Debug header. The plugin
is triggered by the presence of the
X-Debug or the configured header in
the client request. The contents of this header should be the names of the
debug headers that are desired in the response. The XDebug plugin
will remove the
X-Debug header from the client request and
inject the desired headers into the client response.
XDebug is a global plugin. It is installed by adding it to the
plugin.config file. It currently takes a single, optional
This overrides the default
X-Debug header name.
The XDebug plugin is able to generate the following debugging headers:
- If the
Viaheader is requested, the XDebug plugin sets the
proxy.config.http.insert_response_via_strconfiguration variable to
3for the request.
- If the
Diagsheader is requested, the XDebug plugin enables the transaction specific diagnostics for the transaction. This also requires that
proxy.config.diags.debug.enabledis set to
X-Cache-Keyheader contains the URL that identifies the HTTP object in the Traffic Server cache. This header is particularly useful if a custom cache key is being used.
X-Cacheheader contains the results of any cache lookup.
Value Description none No cache lookup was attempted. miss The object was not found in the cache. hit-stale The object was found in the cache, but it was stale. hit-fresh The object was fresh in the cache. skipped The cache lookup was skipped.
- The cache generation ID for this transaction, as specified by the
X-Milestonesheader contains detailed information about how long the transaction took to traverse portions of the HTTP state machine. The timing information is obtained from the
TSHttpTxnMilestoneGet()API. Each milestone value is a fractional number of seconds since the beginning of the transaction.
- A unique transaction ID, which identifies this request / transaction. This matches the log field format that is also available, %<cruuid>.