Error Messages
The following table lists messages that can appear in system log files. This list is not exhaustive; it simply describes common warning messages that can occur and which might require your attention.
Fatal Process Messages
- Accept port is not between 1 and 65535. Please check configuration
- The port specified in - records.yamlthat accepts incoming HTTP requests is not valid.
- Self loop is detected in parent proxy configuration
- The name and port of the parent proxy match that of Traffic Server. This creates a loop when Traffic Server attempts to send the request to the parent proxy. 
Process Warnings
- <Logfile> error: error_number
- Generic logging error. 
- Connect by disallowed client <IP address>, closing
- The specified client is not allowed to connect to Traffic Server; the client IP address is not listed in the - ip_allow.yamlfile.
- Could not rename log <filename> to <rolled filename>
- System error when renaming log file during roll. 
- Log format symbol <symbol name> not found
- Custom log format references a field symbol that does not exist. Refer to Formatting Log Files. 
- Missing field for field marker
- Error reading a log buffer. 
- Unable to open log file <filename>, errno=<error number>
- Cannot open the log file. 
- Error accessing disk <disk name>
- Traffic Server might have a cache read problem. You might need to replace the disk. 
- Too many errors accessing disk <disk name>: declaring disk bad
- Traffic Server is not using the cache disk because it encountered too many errors. The disk might be corrupt and might have to be replaced. 
- No cache disks specified in storage.config file: cache disabled
- The Traffic Server - storage.configfile does not list any cache disks; Traffic Server is running in proxy-only mode. You must add the disks you want to use for the cache to- storage.config.
HTML Messages Sent to Clients
Traffic Server returns detailed error messages to client browsers when there are problems with the HTTP transactions requested by the browser. These Traffic Server response messages correspond to standard HTTP response codes, but provide more information. A list of the more frequently encountered HTTP response codes is provided in HTTP Status Codes.
The error messages can be customized. The actual response is generated from a template. These
templates are stored in files which means the errors responses can be customized by modifying these
files. The default directory for the template files is PREFIX/body_factory/default but this can
be changed by the configuration variable proxy.config.body_factory.template_sets_dir. All
files in this directory are added to a lookup table which is consulted when the error message is
generated. The name used for lookup is by default that listed in the following table. It can be overridden by
proxy.config.body_factory.template_base which, if set, is a string that is prepended to the
search name along with an underscore. For example, if the default lookup name is
cache#read_error then by default the response will be generated from the template in the file
named cache#read_error. If the template base name were set to apache then the lookup would
look for a file named apache_cache#read_error in the template table. This can be used to switch
out error message sets or, because this variable is overridable, to select an error message set
based on data in the transaction. In addition the suffix _default has a special meaning. If
there is a file with the base name and that suffix it is used as the default error page for the base
set, instead of falling back to the global (built in) default page in the case where there is not a
file that matches the specific error. In the example case, if the file apache_default exists
it would be used instead of cache#read_error if there is no apache_cache#read_error.
The text for an error message is processed as if it were a Log Fields which enables customization by values present in the transaction for which the error occurred.
The following table lists the hard-coded Traffic Server HTTP messages, with corresponding HTTP response codes and customizable files.
- Access Denied
- 403You are not allowed to access the document at location- URL.- access#denied
- Cache Read Error
- 500Error reading from cache; please retry request.- cache#read_error
- Connection Timed Out
- 504Too much time has elapsed since the server has sent data.- timeout#inactivity
- Content Length Required
- 411Could not process this request because- Content-Lengthwas not specified.- request#no_content_length
- Cycle Detected
- 400Your request is prohibited because it would cause an HTTP proxy cycle.- request#cycle_detected
- Forbidden
- 403- <port number>is not an allowed port for SSL connections (you have made a request for a secure SSL connection to a forbidden port number).- access#ssl_forbidden
- Host Header Required
- 400An attempt was made to transparently proxy your request, but this attempt failed because your browser did not send an HTTP- Hostheader. Manually configure your browser to use- http://<proxy name>:<proxy port>as the HTTP proxy. Alternatively, end users can upgrade to a browser that supports the HTTP- Hostheader field.- interception#no_host
- Host Header Required
- 400Because your browser did not send a- HostHTTP header field, the virtual host being requested could not be determined. To access the website correctly, you must upgrade to a browser that supports the HTTP- Hostheader field.- request#no_host
- HTTP Version Not Supported
- 505The origin server- <server name>is using an unsupported version of the HTTP protocol.- response#bad_version
- Invalid Content Length
- 400Could not process this request because the specified- Content-Lengthwas invalid (less than 0)..- request#invalid_content_length
- Invalid HTTP Request
- 400Could not process this- <client request>HTTP method request for- URL.- request#syntax_error
- Invalid HTTP Response
- 502The host- <server name>did not return the document- URLcorrectly.- response#bad_response
- Malformed Server Response
- 502The host- <server name>did not return the document- URLcorrectly.- response#bad_response
- Malformed Server Response Status
- 502The host- <server name>did not return the document- URLcorrectly.- response#bad_response
- Maximum Transaction Time exceeded
- 504Too much time has elapsed while transmitting document- URL.- timeout#activity
- No Response Header From Server
- 502The host- <server name>did not return the document- URLcorrectly.- response#bad_response
- Not Cached
- 504This document was not available in the cache, and you (the client) only accept cached copies.- cache#not_in_cache
- Not Found on Accelerator
- 404The request for- URLon host- <server name>was not found. Check the location and try again.- urlrouting#no_mapping
- NULL
- 502The host- <hostname>did not return the document- URLcorrectly.- response#bad_response
- Proxy Authentication Required
- 407Please log in with username and password.- access#proxy_auth_required
- Server Hangup
- 502The server- <hostname>closed the connection before the transaction was completed.- connect#hangup
- Temporarily Moved
- 302The document you requested,- URL, has moved to a new location. The new location is- <new URL>.- redirect#moved_temporarily
- Transcoding Not Available
- 406Unable to provide the document- URLin the format requested by your browser.- transcoding#unsupported
- Tunnel Connection Failed
- 502Could not connect to the server- <hostname>.- connect#failed_connect
- Unknown Error
- 502The host- <hostname>did not return the document- URLcorrectly.- response#bad_response
- Unknown Host
- 500Unable to locate the server named- <hostname>; the server does not have a DNS entry. Perhaps there is a misspelling in the server name or the server no longer exists; double-check the name and try again.- connect#dns_failed
- Unsupported URL Scheme
- 400Cannot perform your request for the document- URLbecause the protocol scheme is unknown.- request#scheme_unsupported
- URI Too Long
- 414Could not process this request because the request uri was too long ..- request#uri_len_too_long