Alerting

How to create an alert for disk usage?

uchoavaz
Explorer

Hello!

 

i am sending from a host to splunk cloud logs from the disk usage. Here is an example how the events are:

 

 

 

/dev/nvme4n1p1	xfs	50G	555M	50G	2%	25M	33K	25M	1%	/var/www

 

 

 

 

where "2%" field is called as "Use_". How can i create an alert/search when this number (without the percentage symbol) is higher than 80 ?

 

Thanks!

Labels (2)
0 Karma
1 Solution

gcusello
SplunkTrust
SplunkTrust

Hi @uchoavaz,

you have to extract the remaining disk space using a regex and then cheate a condition:

index?your_index
| rex "^(?<device>[^ ]+)\s+\w+\s+\w+\s+\w+\s+\w+\s+(?<disk>\d+)"
| where disk>80

You can test the regex at https://regex101.com/r/3W8h6m/1 

Ciao.

Giuseppe

View solution in original post

0 Karma

uchoavaz
Explorer

Worked! Thanks.

0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @uchoavaz,

you have to extract the remaining disk space using a regex and then cheate a condition:

index?your_index
| rex "^(?<device>[^ ]+)\s+\w+\s+\w+\s+\w+\s+\w+\s+(?<disk>\d+)"
| where disk>80

You can test the regex at https://regex101.com/r/3W8h6m/1 

Ciao.

Giuseppe

0 Karma

uchoavaz
Explorer

@gcusello i have an issue here with this regex... it is not filtering  this type of event:

/dev/mapper/group1-mountpoint_www	xfs	9.0G	674M	8.4G	8%	4.5M	33K	4.5M	1%	/var/www

 

basically what changes is the filesystem name (uses "-" and "_") and the size of the numbers and the sizy (M, G, K).

 

PS: I know that in your example the disk needs to be higher than 80, but i changed the value to 2.

0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @uchoavaz,

please try this:

index?your_index
| rex "^(?<device>[^ ]+)(\s+[^ ]+){4}\s+(?<disk>\d+)"
| where disk>80

that you can test at https://regex101.com/r/3W8h6m/3

Ciao.

Giuseppe

0 Karma

uchoavaz
Explorer

I know that the issue is at the dot (".") that can exist or not in the column 3,4 or 5. But how can i put that in the regex?

0 Karma
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