PRTG Manual: Regular Expressions

For some sensors, you can use regular expressions (regex) to match a search pattern. PRTG supports Perl Compatible Regular Expression (PCRE).

The following sensors support regex:

i_round_redYou can only use regex for the respective sensors if you explicitly enable regex in the sensors' settings.

i_round_redPRTG supports regex options in the form (?isgmxUJ) and their negations, for example, (?-i). PRTG does not support regex flags like /g (global), /s (single line), or /gs, and does not correctly search for the target string if you try to set flags.

Common Search Patterns

Find matches that contain the word error or alarm:

\b(error|alarm)\b

Find matches that contain the word ERROR, not error, using case sensitivity:

(?-i)\bERROR\b

Find matches that contain the words error and alarm, in any order:

(?=.*\berror\b)(?=.*\balarm\b).*

Find matches that contain all of the words tree, flower, leaf, and bug, in any order:

(?=.*\btree\b)(?=.*\bflower\b)(?=.*\bleaf\b)(?=.*\bbug\b).*

 
i_round_redIt is not possible to match an empty string with the regex search with sensors.

Example

The search pattern

(?i)(?=.*\berror\b)(?=.*\balarm\b).*

matches the following expressions:

  • Alarm error
  • Error alarm
  • I am an error and I trigger an alarm.
  • I am an alarm and I indicate an error.
  • An alarm combined with an error indeed!
  • An error combined with an alarm, too!

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