Yes, you can use USB storage to increase the log sizes available.
1. Confirm that usb has the logging levels turned on. Log into the cli and check the current setting. This should be the default.
systemname-> get log setting
Levels: 0=Emergency, 1=Alert, 2=Critical, 3=Error, 4=Warning, 5=Notification,
6=Information, 7=Debugging, '-' = disabled
Module Console Internal Email SNMP Syslog
system -------- 01234567 012--5-- 012----- 01234567
Module WebTrends NSM USB
system 012--5-- 01234567 01234567
Serial number is disabled.
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You should see the logging level under USB at 7 and below. If this is not turned on you can set the USB logging level.
systemname-> set log module system level information destination usb
Other levels available are:
emergency,alert,critical,error,warning,notification,information,debugging
2. Enable the logging to the USB device.
systemname-> set log usb enable
This allows the usb stick to be used to the maximum available space. It creates a text file on the drive in the format:
systemname_24Sept2010_log.txt
3. To restrict the size of the log file.
systemname-> set log usb filesize ## (number of megabytes)
4. Viewing the logs
These logs are visible in the web and cli interface while they are gathered. To remove the device for review on you computer.
systemname-> unset log usb enable
systemname-> exec usb-device stop