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Teemu_Kunnari_1's avatar
Teemu_Kunnari_1
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Jul 02, 2018

ASM Local storage logging

Hello,

 

I would like to know how what is the default ASM Log buffer size (local storage / f5 system) for Event Logs regarding ASM if you choose the option etc. Log illegal requests? And how long they are stored in the system?

 

Thanks in advance!

 

BR

 

Teemu

 

1 Reply

  • Hi,

     

    You have to know that in versions prior to BIG-IP ASM 11.6.0, the system writes security events to the /var/log/asm file by default using syslog.

     

    eginning in BIG-IP ASM 11.6.0, enhancements were introduced to improve system performance and stability. As a result, the system no longer writes security events to syslog by default and it does not log them locally to the /var/log/asm file. You may enable the send_content_events internal parameter to replicate the old behavior. However, F5 recommends leaving it disabled due to a potential decrease in performance.

     

    For more information: https://support.f5.com/csp/article/K16053

     

    In all case I advise you to send your ASM logs to a syslog server. In this case you can manage your logs (retention policy, ...)

     

    Regarding event logs that you can see in GUI, SM will locally hold up to 3 Million log entries, or 2 GB of data, whichever comes first. On device logging is probably best used for troubleshooting and short-term forensics, and an external logging facility is best used for long-term logging.

     

    Fore more info:

     

    https://devcentral.f5.com/questions/asm-request-event-correlation-differencies

     

    https://support.f5.com/kb/en-us/products/big-ip_asm/manuals/product/asm-config-11-2-0/asm_monitoring.html?sr=528965261055514

     

    Regards