Understanding the fs file for a jail

[grahamperrin]

Background

Long ago, my boot pool was named copperbowl.

In August 2021, I replaced the hard disk drive, the pool name is august.

A few hours ago, I performed some long overdue housekeeping and reorganisation, including this rename of a jail and rename of a file system:

root@mowa219-gjp4-8570p-freebsd:~ # poudriere jail -r 13r -j 13
[00:00:00] Renaming '13' in '13r' done
[00:00:03] Warning: The packages, logs and filesystems have not been renamed.
[00:00:03] Warning: If you choose to rename the filesystem then modify the 'mnt' and 'fs' files in /usr/local/etc/poudriere.d/jails/13r
root@mowa219-gjp4-8570p-freebsd:~ # zfs rename august/poudriere/jails/example august/poudriere/jails/13r
root@mowa219-gjp4-8570p-freebsd:~ # poudriere jail -l
JAILNAME VERSION              ARCH  METHOD       TIMESTAMP           PATH
13r      13.0-RELEASE-p4      amd64 http         2021-09-21 22:18:57 /usr/local/poudriere/jails/example
main     14.0-CURRENT 1400053 amd64 src=/usr/src 2022-02-23 02:17:02 /usr/local/poudriere/jails/main
root@mowa219-gjp4-8570p-freebsd:~ # 

I took the hint to edit /usr/local/etc/poudriere.d/jails/13r/mnt, after which poudriere jail -u -j 13r succeeded.

Question

Please, what are the consequences of not editing the fs file?

I ask because today I realised that for the past few months, it seems that my main jail has worked with an fs file that is outdated or invalid:

root@mowa219-gjp4-8570p-freebsd:~ # grep -r -i copperbowl /usr/local/etc/poudriere.d/jails
/usr/local/etc/poudriere.d/jails/13r/fs:copperbowl/poudriere/jails/example
/usr/local/etc/poudriere.d/jails/main/fs:copperbowl/poudriere/jails/main
root@mowa219-gjp4-8570p-freebsd:~ # 

• copperbowl no longer exists.