======How to Obtain Error Logs======

As part of diagnosing a support issue our support team may ask you to send them various log files. This page explains how to obtain the right files at the right time.

=====How Logging Works=====
Under its default settings VPOP3 logs a minimal amount of information about what it is doing to various files in the main VPOP3 directory. When investigating a support issue it is often the case that we will need you to switch on logging to extra files or increase the level of detail being written to the main log. This can generate a lot of data; up to several MB per second. In order to prevent disks getting filled up with logged data VPOP3 limits the maximum size of these log files. By default this size is set to 1MB but can be increased in ''Settings -> Diagnostics''. Once the files reach their maximum size they are renamed with a ''.lbk'' extension (''.old'' in versions prior to 2.4.7) and a new ''.log'' file is started.

=====Where the Log Files Are=====
The log files will be found in the directory specified under ''Settings -> Diagnostics -> General -> Log Path''. By default, generally speaking in older versions of vPOP3 you'll find the log files in the main VPOP3 directory. In newer versions you may find the log files in the ''_log'' subdirectory within the main VPOP3 directory. The exact rules for deciding where the log files are stored depends on your upgrade history and what settings changes you have made. 

=====The Right Files=====
The main log files of interest have the following as the first part of their filename (before the ''.log'' or ''.lbk'' extension):

^Filename ^What we call it ^Contains ^
|vpop3 |Main VPOP log |The main VPOP3 log file |
|errors |Error log |A subset of the vpop3 log file which only contains errors |
|security |Security log |Information relating to failed logins and the like |
|smtpclt |SMTP client log |Session commands and data when VPOP3 is sending to another SMTP server (e.g. ISP) |
|smtpsvr |SMTP server log |Session commands and data when VPOP3 is receiving outbound mail from a mail client (e.g. Outlook) |
|pop3clt |POP3 client log |Session commands and data when VPOP3 is retrieving mail from a POP3 server (e.g. ISP mailbox) |
|pop3svr |POP3 server log |Session commands and data when VPOP3 is sending inbound mail to a POP3 mail client (e.g. Outlook mailbox) |
|imap4svr |IMAP server log |Session commands and data when VPOP3 is sending inbound mail to an IMAP4 mail client (e.g. Outlook mailbox) |

When we need to see log files we'll let you know exactly which files we need.

=====The Right Time=====
Most of the time it's easy enough to catch the right data in the log files but on a busy server there can be so much data being written to the logs that you need to be pretty quick to grab the data from the logs before they are overwritten. Here's the general approach that works well in all cases:

  - Switch on any of the session logs (e.g. ''smtpclt'', ''imap4svr'' etc.) you've been asked for on the ''Settings -> Diagnostics -> Sessions'' page.
  - Set the maximum size of these files to an appropriate value (10MB is good for a busy VPOP3 installation) on the ''Settings -> Diagnostics -> Sessions'' page.
  - Set ''Settings -> Diagnostics -> General -> Log Level'' to ''Full Logging'' if you've been asked for a VPOP3 log on full logging.
  - Set the maximum size of the main VPOP3 log file to an appropriate value (10MB is good for a busy VPOP3 installation) using ''Settings -> Diagnostics -> General -> Maximum log size'' page.
  - Perform the actions necessary to trigger the problem you're trying to solve.
  - Immediately the problem occurs copy the relevant log files to a temporary directory to avoid the data being overwritten by subsequent data.
  - Send us the log files.

{{tag>error log diagnostic}}