I followed these instructions..
Go to Settings->Network Services->Syslog Server
You can click on the 'Help' icon on the Toolbar and get more information for all of the options.
Mirror to Flash: This is the simplest to set up. You select 'Yes' from the dropdown box and click on the 'Apply' button and the syslog will be mirrored to the logs folder/directory of the flash drive and is appended to on a reboot. There is one principal disadvantage to this method. If the condition, that you are trying to troubleshoot, takes days to weeks to occur, it can do a lot of writes to the flash drive. Some folks are hesitant to use the flash drive in this manner as it may shorten the life of the flash drive.
The advantage of this approach is that it captures everything from the start of the boot process which can be important if trying to diagnose boot problems.
Have i missed something ?...i hard shut down the server as it had crashed and then removed the flash drive to get the file off.