How I can extract this value from hostname with regex_replace like this.
I have regex_replace
"{{ inventory_hostname | regex_replace('^\\D+|\\..*', '') }}"
And hostname like this
nginx09-2.domain.com
And I want extract only number after - (2), but my regex_replace extracing 09-2.
You can capture the number and replace the string with it:
"{{ inventory_hostname | regex_replace('^.*-(\\d+).*$', '\\1') }}"
- debug:
msg: "{{ 'nginx09-2.domain.com' | regex_replace('^.*-(\\d+).*$', '\\1') }}"
# 2
You can extend your pattern a bit to match the first number and -
"{{ inventory_hostname | regex_replace('^\\D+\\d+-|\\..*', '') }}"
See the regex demo
Details
^\D+\d+- - a start of string (^), then one or more chars other than a digit (\D+), then one or more digits (\d+) and a - char| - or\..* - a dot (\.) and then the rest of the string (.*).