Diff of the two buildlogs:

--
--- b1/build.log	2024-01-06 22:16:22.737500518 +0000
+++ b2/build.log	2024-01-06 22:16:55.980081843 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sat Jan  6 10:12:58 -12 2024
-I: pbuilder-time-stamp: 1704579178
+I: Current time: Sat Feb  8 18:39:28 +14 2025
+I: pbuilder-time-stamp: 1738989568
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bullseye-reproducible-base.tgz]
 I: copying local configuration
@@ -17,7 +17,7 @@
 I: copying [./libident_0.22-3.1.diff.gz]
 I: Extracting source
 gpgv: unknown type of key resource 'trustedkeys.kbx'
-gpgv: keyblock resource '/tmp/dpkg-verify-sig.J8nDGttQ/trustedkeys.kbx': General error
+gpgv: keyblock resource '/tmp/dpkg-verify-sig.zqS3J9U1/trustedkeys.kbx': General error
 gpgv: Signature made Fri Nov 11 13:34:10 2016 
 gpgv:                using RSA key C2FE4BD271C139B86C533E461E953E27D4311E58
 gpgv: Can't check signature: No public key
@@ -39,49 +39,80 @@
  libident-0.22/version.c
 I: using fakeroot in build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/1870974/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/D01_modify_environment starting
+debug: Running on ionos5-amd64.
+I: Changing host+domainname to test build reproducibility
+I: Adding a custom variable just for the fun of it...
+I: Changing /bin/sh to bash
+'/bin/sh' -> '/bin/bash'
+lrwxrwxrwx 1 root root 9 Feb  8 04:39 /bin/sh -> /bin/bash
+I: Setting pbuilder2's login shell to /bin/bash
+I: Setting pbuilder2's GECOS to second user,second room,second work-phone,second home-phone,second other
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/D02_print_environment starting
 I: set
-  BUILDDIR='/build/reproducible-path'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
-  BUILD_ARCH='amd64'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all,-fixfilepath parallel=15 '
-  DISTRIBUTION='bullseye'
-  HOME='/root'
-  HOST_ARCH='amd64'
+  BASH=/bin/sh
+  BASHOPTS=checkwinsize:cmdhist:complete_fullquote:extquote:force_fignore:globasciiranges:hostcomplete:interactive_comments:progcomp:promptvars:sourcepath
+  BASH_ALIASES=()
+  BASH_ARGC=()
+  BASH_ARGV=()
+  BASH_CMDS=()
+  BASH_LINENO=([0]="12" [1]="0")
+  BASH_SOURCE=([0]="/tmp/hooks/D02_print_environment" [1]="/tmp/hooks/D02_print_environment")
+  BASH_VERSINFO=([0]="5" [1]="1" [2]="4" [3]="1" [4]="release" [5]="x86_64-pc-linux-gnu")
+  BASH_VERSION='5.1.4(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=amd64
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all,-fixfilepath parallel=16 '
+  DIRSTACK=()
+  DISTRIBUTION=bullseye
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=x86_64
+  HOST_ARCH=amd64
   IFS=' 	
   '
-  INVOCATION_ID='b021e63d432240e28edd53f4fb012c2f'
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  MAIL='/var/mail/root'
-  OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
-  PBCURRENTCOMMANDLINEOPERATION='build'
-  PBUILDER_OPERATION='build'
-  PBUILDER_PKGDATADIR='/usr/share/pbuilder'
-  PBUILDER_PKGLIBDIR='/usr/lib/pbuilder'
-  PBUILDER_SYSCONFDIR='/etc'
-  PPID='1870974'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=3d19e8ce6aa4485596703153f075ff1d
+  LANG=C
+  LANGUAGE=et_EE:et
+  LC_ALL=C
+  MACHTYPE=x86_64-pc-linux-gnu
+  MAIL=/var/mail/root
+  OPTERR=1
+  OPTIND=1
+  OSTYPE=linux-gnu
+  PATH=/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path
+  PBCURRENTCOMMANDLINEOPERATION=build
+  PBUILDER_OPERATION=build
+  PBUILDER_PKGDATADIR=/usr/share/pbuilder
+  PBUILDER_PKGLIBDIR=/usr/lib/pbuilder
+  PBUILDER_SYSCONFDIR=/etc
+  PIPESTATUS=([0]="0")
+  POSIXLY_CORRECT=y
+  PPID=2154376
   PS4='+ '
-  PWD='/'
-  SHELL='/bin/bash'
-  SHLVL='2'
-  SUDO_COMMAND='/usr/bin/timeout -k 18.1h 18h /usr/bin/ionice -c 3 /usr/bin/nice /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.92gspzdl/pbuilderrc_mXWn --distribution bullseye --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bullseye-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.92gspzdl/b1 --logfile b1/build.log libident_0.22-3.1.dsc'
-  SUDO_GID='110'
-  SUDO_UID='105'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://78.137.99.97:3128'
+  PWD=/
+  SHELL=/bin/bash
+  SHELLOPTS=braceexpand:errexit:hashall:interactive-comments:posix
+  SHLVL=3
+  SUDO_COMMAND='/usr/bin/timeout -k 24.1h 24h /usr/bin/ionice -c 3 /usr/bin/nice -n 11 /usr/bin/unshare --uts -- /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.92gspzdl/pbuilderrc_L7hj --distribution bullseye --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bullseye-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.92gspzdl/b2 --logfile b2/build.log libident_0.22-3.1.dsc'
+  SUDO_GID=110
+  SUDO_UID=105
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://85.184.249.68:3128
 I: uname -a
-  Linux ionos1-amd64 6.1.0-17-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.69-1 (2023-12-30) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.5.0-0.deb12.4-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.5.10-1~bpo12+1 (2023-11-23) x86_64 GNU/Linux
 I: ls -l /bin
   total 5476
   -rwxr-xr-x 1 root root 1234376 Mar 27  2022 bash
@@ -141,7 +172,7 @@
   -rwxr-xr-x 1 root root   52032 Sep 24  2020 rmdir
   -rwxr-xr-x 1 root root   27472 Sep 27  2020 run-parts
   -rwxr-xr-x 1 root root  122224 Dec 22  2018 sed
-  lrwxrwxrwx 1 root root       4 Dec  7 09:24 sh -> dash
+  lrwxrwxrwx 1 root root       9 Feb  8 04:39 sh -> /bin/bash
   -rwxr-xr-x 1 root root   43808 Sep 24  2020 sleep
   -rwxr-xr-x 1 root root   84928 Sep 24  2020 stty
   -rwsr-xr-x 1 root root   71912 Jan 20  2022 su
@@ -167,7 +198,7 @@
   -rwxr-xr-x 1 root root    2206 Apr 10  2022 zless
   -rwxr-xr-x 1 root root    1842 Apr 10  2022 zmore
   -rwxr-xr-x 1 root root    4577 Apr 10  2022 znew
-I: user script /srv/workspace/pbuilder/1870974/tmp/hooks/D02_print_environment finished
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -209,7 +240,11 @@
 fakeroot is already the newest version (1.25.3-1.1).
 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/reproducible-path/libident-0.22/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-genchanges -S  > ../libident_0.22-3.1_source.changes
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for bullseye
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/libident-0.22/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-genchanges -S  > ../libident_0.22-3.1_source.changes
 dpkg-buildpackage: info: source package libident
 dpkg-buildpackage: info: source version 0.22-3.1
 dpkg-buildpackage: info: source distribution unstable
@@ -416,12 +451,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: not including original source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/2154376/tmp/hooks/B01_cleanup finished
 I: unmounting dev/ptmx filesystem
 I: unmounting dev/pts filesystem
 I: unmounting dev/shm filesystem
 I: unmounting proc filesystem
 I: unmounting sys filesystem
 I: cleaning the build env 
-I: removing directory /srv/workspace/pbuilder/1870974 and its subdirectories
-I: Current time: Sat Jan  6 10:16:21 -12 2024
-I: pbuilder-time-stamp: 1704579381
+I: removing directory /srv/workspace/pbuilder/2154376 and its subdirectories
+I: Current time: Sat Feb  8 18:39:57 +14 2025
+I: pbuilder-time-stamp: 1738989597