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Cisco ASA: How to limit ASA logs being logged to Splunk cloud

nkingsbury
Engager

Hello,
I am trying to get my firewall logs into our Splunk cloud instance, but I have concerns about the log size I am seeing being created. Currently, the syslog-ng file is growing at about 200M per hour, so 5.8G per day. That's one firewall out of 6. Our currently daily limit is 5G a day. Obviously we will have to increase the limit, but I am trying to reduce the over all size the firewalls log.

Do most of you log all info into Splunk and just pay for the massive amounts of data per day, or is there good pruning schemes that are common?
I have added the following to the firewall to try to reduce excess noise, but now I think most of the logs are generated from the SFR modules:

no logging message 305010
no logging message 305011
no logging message 305012
no logging message 302014
no logging message 302016
no logging message 302013

Any advice would be appreciated.

0 Karma

hmarkus
Explorer

You could use Heavy Forwarder or build a App for Splunk Cloud to filter your Logs. If you know, how your unnecessary Logs look like, you can filter it:
add in props.conf
TRANSFORMS-asa_filter_cloud = filterAsaLogs
add in transforms.conf
[filterAsaLogs]
SOURCE_KEY = _raw
DEST_KEY = queue
FORMAT = nullQueue
REGEX = (your regex to detect them)

0 Karma
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