Getting Data In

Using an IP range in Inputs.conf

bongski
Engager

Hey,

I was hoping someone can clarify if an IP range to subnet can be used in Inputs.conf.

For example all hosts on

192.168.1.0/24 (192.168.1.0-192.168.1.254) go to index A.

192.168.2.0/24 (192.168.2.0-192.168.2.254) goes to index B.

I have read though the documentation but I can't seem to find anything. Also if it is possible what is the correct syntax for the file?

[tcp://192.168.1.0/24:5000]

[tcp://192.168.1.0-192.168.1.254:5000]

If I have missed something in the documentation I apologise.

Tags (2)
0 Karma
1 Solution

lguinn2
Legend

I do not believe this possible. However, you can redirect inputs to different indexes, just not with inputs.conf. Here is how:

inputs.conf

[tcp://:5000]
connection_host = ip
sourcetype = mixedinputs
index=defaultIndex

props.conf

[mixedinputs]
TRANSFORM=separate_inputs1, separate_inputs2

transforms.conf

[separate_inputs1]
SOURCE_KEY=MetaData:Host
REGEX=host::192\.168\.1\.1
DEST_KEY=_MetaData:Index
FORMAT=A

[separate_inputs2]
SOURCE_KEY=MetaData:Host
REGEX=host::10\.1\.\d+\.\d+
DEST_KEY=_MetaData:Index
FORMAT=B

First, this assigns all inbound events from port 5000 to defaultIndex (whatever you want to call it). Then, as the data is processed, each event is examined. If the host field (ip) of an event matches the regular expression (REGEX), the event is reassigned to the index named in FORMAT.

Note that you can write the REGEX to "wildcard" the octets, but I don't now how to use CIDR notation with regular expressions.

View solution in original post

lguinn2
Legend

I do not believe this possible. However, you can redirect inputs to different indexes, just not with inputs.conf. Here is how:

inputs.conf

[tcp://:5000]
connection_host = ip
sourcetype = mixedinputs
index=defaultIndex

props.conf

[mixedinputs]
TRANSFORM=separate_inputs1, separate_inputs2

transforms.conf

[separate_inputs1]
SOURCE_KEY=MetaData:Host
REGEX=host::192\.168\.1\.1
DEST_KEY=_MetaData:Index
FORMAT=A

[separate_inputs2]
SOURCE_KEY=MetaData:Host
REGEX=host::10\.1\.\d+\.\d+
DEST_KEY=_MetaData:Index
FORMAT=B

First, this assigns all inbound events from port 5000 to defaultIndex (whatever you want to call it). Then, as the data is processed, each event is examined. If the host field (ip) of an event matches the regular expression (REGEX), the event is reassigned to the index named in FORMAT.

Note that you can write the REGEX to "wildcard" the octets, but I don't now how to use CIDR notation with regular expressions.

lguinn2
Legend

Yeah, the event-by-event processing will always cost more resources than the "index the whole input stream from this port" method. There is always a trade-off 😉

0 Karma

bongski
Engager

This worked great, the solution is a bit CPU intensive but worked exactly how I needed it to.

0 Karma

MuS
SplunkTrust
SplunkTrust

why not just use the index stanza in inputs.conf on the forwarder, should work as well.

0 Karma

bongski
Engager

Thanks for the tip, I will impletment it that way and let you know how I go.

0 Karma
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