/etc/logcheck/ignore.d.server/schroot is in logcheck-database 1.3.14.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | ^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ schroot\[[[:digit:]]+\]: (\(pam_unix\)|pam_unix\(schroot:session\):) session opened for user [-_.[:alnum:]]+ by ([-_.[:alnum:]]+)?\(uid=[[:digit:]]+\)$
^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ schroot\[[[:digit:]]+\]: \[[-._[:alnum:]]+ chroot\] \([-_.[:alnum:]]+->[-_.[:alnum:]]+\) Running login shell: '[-._/[:alnum:]]+'$
^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ schroot\[[[:digit:]]+\]: \[[-._[:alnum:]]+ chroot\] \([-_.[:alnum:]]+->[-_.[:alnum:]]+\) Running command: ".+"$
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