Multiple search
In regex, it is possible to simultaneously request multiple searches with the logical OR operator. In this example we will see the possibility of using multiple search filters in regexp options.
Symbole | Signification |
| '^((word|word1)$)' | Requesting specifically word and word1 resources |
| '^((word|word1.*)$)' | Requesting word resources and all resources beginning by word1 |
Check '/' and ‘/var/log’ Disk partitions
By overriding the --storage option with the filter '^(/|/var/log)$', I ask to exclude all disks on my linux server starting with '/var/'
-bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=storage --hostname=localhost --snmp-version='2c' --snmp-community='public' --storage='^(/|/var/lib)$' --name --regexp --display-transform-src='' --display-transform-dst='' --warning-usage='80' --critical-usage='90' --verbose --filter-perfdata='storage.space|used|free'
OK: All storages are ok | 'used_/'=4859703296B;0:7990987980;0:8989861478;0;9988734976 'used_/var/lib'=7819071488B;0:7990987980;0:8989861478;0;9988734976
Storage '/' Usage Total: 9.30 GB Used: 4.53 GB (48.65%) Free: 4.78 GB (51.35%)
Storage '/var/lib' Usage Total: 9.30 GB Used: 7.28 GB (78.28%) Free: 2.02 GB (21.72%)
Check the status of processes 'cbd' and ‘centengine’.
By overriding the --process-name option with the '^(cbd|centengine)$' filter, I include cbd and centengine processes in my command line
-bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=processcount --hostname=10.25.5.88 --snmp-version='2c' --snmp-community='public' --process-name='^(cbd|centengine)$' --process-path='' --process-args='' --regexp-name --regexp-path --regexp-args --warning='' --critical='1:' --cpu --memory --verbose
OK: Number of current processes running: 3 - Total memory usage: 32.50 MB - Average memory usage: 10.83 MB - Total CPU usage: 1.48 % | 'nbproc'=3;;1:;0; 'mem_total'=34082816B;;;0; 'mem_avg'=11360938.67B;;;0; 'cpu_total'=1.48%;;;0;
Process '29050' [memory: 2.92 MB] [cpu: 0.36 %] [status: runnable] [name: cbd]
Process '15108' [memory: 4.96 MB] [cpu: 0.15 %] [status: runnable] [name: centengine]
Process '29049' [memory: 24.62 MB] [cpu: 0.97 %] [status: runnable] [name: cbd]
We can resume the usage of multiple search by referencing this options below:
Mode | Regexp Options Centreon-Plugins | Signification |
| Disk | --storage='^(/|/var/lib)$' --name --regexp | Matching both the /var/lib and / partition |
| Process | --process-name='^(cbd|centengine)$' --process-path='' --process-args='' --regexp-name --regexp-path --regexp-args | Matching specifically the processus “cbd” using –process-name and –process-path options with –regexp-name and –regexp-path |
Data exclusion
In regex, it is possible to exclude certain information from the search. In this example we will see the possibility of using exclusion filters in the regexp options.
If we want to exclude a specific resource in a dataset, we can apply a filter using the symbols ('?','!','.','*') as in the table below
Symbole | Signification |
| '^(?!word$)' | Specifically exclude the resource word in our check |
| '^(?!word.*$)' | Exclude all resources starting with word in our check |
| '^(?!(word|word1)$)' | Exclude all multiples resources word and word1 |
Control of all network interfaces excluding the loopback card
By overriding the --interface option with the '^(?!lo$)' filter, I ask to exclude all network cards on my linux server using the name 'lo'
-bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=interfaces --hostname=localhost --snmp-version='2c' --snmp-community='public' --interface='^(?!lo$)' --name --add-status --add-traffic --critical-status='' --warning-in-traffic='80' --critical-in-traffic='90' --warning-out-traffic='80' --critical-out-traffic='90' --verbose
OK: Interface 'eth0' Status : up (admin: up), Traffic In : 10.15Kb/s (-), Traffic Out : 15.47Kb/s (-) | 'traffic_in'=10154.67b/s;;;0; 'traffic_out'=15472.00b/s;;;0;
Interface 'eth0' Status : up (admin: up), Traffic In : 10.15Kb/s (-), Traffic Out : 15.47Kb/s (-)
Check all partitions excluding all '/var/' partitions
By overriding the --storage option with the filter '^(?!/var/)', I ask to exclude all disks on my linux server starting with '/var/'
-bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=storage --hostname=localhost --snmp-version='2c' --snmp-community='public' --storage='^(?!/var/)' --name --regexp --display-transform-src='' --display-transform-dst='' --warning-usage='80' --critical-usage='90' --verbose --filter-perfdata='storage.space|used|free'
OK: All storages are ok | 'used_/dev/shm'=0B;0:770165964;0:866436710;0;962707456 'used_/run'=25669632B;0:770165964;0:866436710;0;962707456 'used_/sys/fs/cgroup'=0B;0:770165964;0:866436710;0;962707456 'used_/'=2326142976B;0:7990987980;0:8989861478;0;9988734976 'used_/boot'=224030720B;0:796632678;0:896211763;0;995790848 'used_/run/user/1000'=0B;0:154035814;0:173290291;0;192544768
Storage '/dev/shm' Usage Total: 918.11 MB Used: 0.00 B (0.00%) Free: 918.11 MB (100.00%)
Storage '/run' Usage Total: 918.11 MB Used: 24.48 MB (2.67%) Free: 893.63 MB (97.33%)
Storage '/sys/fs/cgroup' Usage Total: 918.11 MB Used: 0.00 B (0.00%) Free: 918.11 MB (100.00%)
Storage '/' Usage Total: 9.30 GB Used: 2.17 GB (23.29%) Free: 7.14 GB (76.71%)
Storage '/boot' Usage Total: 949.66 MB Used: 213.65 MB (22.50%) Free: 736.01 MB (77.50%)
Storage '/run/user/1000' Usage Total: 183.62 MB Used: 0.00 B (0.00%) Free: 183.62 MB (100.00%)
Check the status of all processes excluding 'cbd'.
By overriding the --process-name option with the '^(?!cbd$)' filter, I ask to exclude all processes on my linux server containing the word 'cbd
-bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=processcount --hostname=10.25.5.88 --snmp-version='2c' --snmp-community='public' --process-name='^(?!cbd$)' --process-path='' --process-args='' --regexp-name --regexp-path --regexp-args --warning='' --critical='1:' --cpu --memory --verbose
OK: Number of current processes running: 118 - Total memory usage: 1003.08 MB - Average memory usage: 8.50 MB - Total CPU usage: 0.75 % | 'nbproc'=118;;1:;0; 'mem_total'=1051803648B;;;0; 'mem_avg'=8913590.24B;;;0; 'cpu_total'=0.75%;;;0;
Process '33' [memory: 0.00 B] [cpu: 0.00 %] [status: runnable] [name: ksmd]
Process '32' [memory: 0.00 B] [cpu: 0.00 %] [status: runnable] [name: kswapd0]
Process '7887' [memory: 36.82 MB] [cpu: 0.00 %] [status: runnable] [name: gorgone-proxy]
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We can resume the usage of exclusion search by referencing this options below:
Mode | Regexp Options Centreon-Plugins | Signification |
| Traffic | --interface='^(?!lo$)' --name | Excluding localhost interface |
| Disk | --storage='^(?!/var/)' --name --regexp | Excluding all /var/lib/* partitions. Example: /var/lib/centreon, /var/lib/centreon-broker, etc |
| Process | --process-name='^(?!cbd$)' --process-path='' --process-args='' --regexp-name --regexp-path --regexp-args | Excluding cbd process |
To resume
We have seen through some examples, and explored the possibilities of using regexes in Centreon-Plugins options. We can resume differents bases and use case in this table as below:
Symbole | Signification |
| . + * ? ^ $ ( ) [ ] { } | \ | These characters have special meaning in regex |
| . | Anyone character except newline |
| * | The preceding item will be matched zero or more times |
| ? | The preceding item is optional and matched at most once (0 or 1 time) |
| | | This character is used to separate multiples possibilities |
| \ | To match a character having special meaning in regex, you need to use a escape sequence prefix with a backslash You also need to use regex \\ to match "\" (back-slash). |
| [] | Accept ANY ONE of the character within the square bracket |
Examples | Signification |
| .* | Every characters |
| ^word$ | Search exact word resource |
| ^word | Search all resource beginning by word |
| word$ | Search all resource ending by word |
| ^word|word1$ | Search word and word1 resources |
| ^(?!word$) | Exclude word resource |
| ^(?!(word|word1)$) | Exclude word and word1 resources |
Reminder of the Regexp characters used, to go further, do not hesitate to visit the Perl for Regexp website : https://perldoc.perl.org/perlre
Reminder for Traffic Mode
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The use of the 'interface' mode corresponds to the Traffic mode in Centreon.
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It requires the use of the "--interface --name" options to use regular expressions.
The 'interface' mode help shows you the use of the regexp options seen earlier
| /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=interfaces --help --interface Set the interface (number expected) ex: 1,2,... (empty means 'check all interface'). --name Allows to use interface name with option --interface instead of interface oid index (Can be a regexp) |
Reminder for Disk mode
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The use of the storage mode corresponds to the Disk mode in Centreon.
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It requires the options "--storage --name --regexp" to use regular expressions.
The help of this mode allows to help you on the use of these options
| -bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=storage --help --storage Set the storage (number expected) ex: 1, 2,... (empty means 'check all storage'). --name Allows to use storage name with option --storage instead of storage oid index. --regexp Allows to use regexp to filter storage (with option --name). |
Reminder for Process mode
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The use of the processcount mode corresponds to the Process mode in Centreon.
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It requires at least the "--process-name --regexp-name" option and if necessary additional options "--process-path --process-args --regexp-path --regexp-args" to use regular expressions.
The help of this mode allows you to make the best use of all these options
| -bash-4.2$ /usr/lib/centreon/plugins//centreon_linux_snmp.pl --plugin=os::linux::snmp::plugin --mode=processcount --help --process-name Filter process name. --regexp-name Allows to use regexp to filter process name (with option --process-name). --process-path Filter process path. --regexp-path Allows to use regexp to filter process path (with option --process-path). --process-args Filter process arguments. --regexp-args Allows to use regexp to filter process arguments (with option --process-args). |
