Getting Data In

Are there performance implications of using props.conf and transforms.conf to change Index and SourceType?

feisar
Explorer

Hi,

I'm new to Splunk and have installed the Enterprise trial on Windows and pointed two Cisco ASA firewalls at it. Logs are coming through fine and I've used props.conf and transforms.conf to tag them with an appropriate Index and SourceType.

props.conf

[host::192.168.5.2]
TRANSFORMS-firewall_cisco = set_index_firewall_cisco_asa, set_sourcetype_firewall_cisco_asa

[host::192.168.6.2]
TRANSFORMS-firewall_cisco = set_index_firewall_cisco_asa, set_sourcetype_firewall_cisco_asa

transforms.conf

[set_index_firewall_cisco_asa]
DEST_KEY = _MetaData:Index
FORMAT = firewall_cisco
REGEX = .

[set_sourcetype_firewall_cisco_asa]
DEST_KEY = MetaData:Sourcetype
FORMAT = sourcetype::cisco:asa
REGEX = .

My question is about the scaleability of my configuration. It seems a little clunky to have to edit the config in the way that I have for each and every device I want Splunk to retrieve the logs of over the deafult TCP Syslog port. (I'm assuming I will want a different Index and SourceType for each device type).

  • Is there a performace hit with the config I have used (if so, is it big enough to worry about)?

  • Can anyone suggest a better way of achieving what I want?

Thanks : )

0 Karma
1 Solution

tskinnerivsec
Contributor

An easier method, as opposed to doing this for each host is to use in your regex %ASA which is included in every cisco asa event. Then in your props.conf you can just use :

[source::udp:514] (assuming you are receiving the data straight from syslog
TRANSFORMS-firewall_cisco = set_index_firewall_cisco_asa, set_sourcetype_firewall_cisco_asa

Then you won't have to configure it for each and every firewall, it will only apply to syslog data that contains the string %ASA in it. Also, will be more efficient, since your regex is more specific than "."

View solution in original post

tskinnerivsec
Contributor

An easier method, as opposed to doing this for each host is to use in your regex %ASA which is included in every cisco asa event. Then in your props.conf you can just use :

[source::udp:514] (assuming you are receiving the data straight from syslog
TRANSFORMS-firewall_cisco = set_index_firewall_cisco_asa, set_sourcetype_firewall_cisco_asa

Then you won't have to configure it for each and every firewall, it will only apply to syslog data that contains the string %ASA in it. Also, will be more efficient, since your regex is more specific than "."

Get Updates on the Splunk Community!

Enter the Agentic Era with Splunk AI Assistant for SPL 1.4

  🚀 Your data just got a serious AI upgrade — are you ready? Say hello to the Agentic Era with the ...

Feel the Splunk Love: Real Stories from Real Customers

Hello Splunk Community,    What’s the best part of hearing how our customers use Splunk? Easy: the positive ...

Data Management Digest – November 2025

  Welcome to the inaugural edition of Data Management Digest! As your trusted partner in data innovation, the ...