Getting Data In

Cannot change host field in syslog data

sunrise
Contributor

Hi Splunkers,

I collect syslog(/var/log/messages) data by Universal Forwarder, not UDP like this.
Sep 3 12:42:16 ip-111-111-111-111 dhclient: bound to 111.111.111.111 -- renewal in 1414 seconds.

And I want to get this host field as FQDN "myhost", but I cannot do this.
Configuration files in indexers as following.

inputs.conf
[monitor:///var/log/messages]
index = mysyslog
host = myhost

props.conf
[host::ip-111-111-111-111]
TRANSFORMS-t1 = rename_myhost

transforms.conf
[rename_myhost]
REGEX = ^.*$
DEST_KEY = MetaData:Host
FORMAT = host::myhost

How can I will do this ?

Thank you for your help.

1 Solution

HiroshiSatoh
Champion

inputs.confでhostを指定するのではダメですか?

例)
[monitor:///var/log/messages]
disabled = false
sourcetype = syslog
host = myhost

View solution in original post

HiroshiSatoh
Champion

inputs.confでhostを指定するのではダメですか?

例)
[monitor:///var/log/messages]
disabled = false
sourcetype = syslog
host = myhost

kristian_kolb
Ultra Champion

The problem is that while host=myhost is set in the input phase, data with the syslog sourcetype will be sent to a transform that rewrites the hostname to whatever comes after the timestamp in each event.

If you change the sourcetype to something other than syslog this host override will not happen.

/k

saurabh_tek11
Communicator

@sunrise, @HiroshiSatoh @kristian.kolb Still it is unclear to me what would be correct settings in inputs, props and transforms.conf

is this correct ??
please correct me if i am not getting it right. Thanks for help!

inputs.conf
[monitor:///var/log/messages]
index = mysyslog
disabled = false
sourcetype = syslog
host = myhost

props.conf
[syslog]
TRANSFORMS-t1 = rename_myhost

transforms.conf
[rename_myhost]
REGEX = ^.*$
DEST_KEY = MetaData:Host
FORMAT = host::myhost
0 Karma

micahkemp
Champion

The above looks correct, but there is already a TRANSFORMS = syslog-host defined by default for the syslog sourcetype, which might occur after your transform, thus rewriting the host field again based on the contents of the syslog message.

0 Karma

sunrise
Contributor

No I cannot do by that way.
I've already set host=myhost in inputs.conf file.

0 Karma
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