Hi. I sent below mail some week ago, Barry's reply left me unsure as to whether this would be a bug or not. I still tend do assume that I'm "doing something wrong". So before I open an issue on GitHub, I'll give it another try here. Thanks. I'm playing with the LogFilterPatterns= directive on user-level services, not very successfully so far. [~]$ systemd --version systemd 255 (255.2-3) +PAM +AUDIT +SELINUX +APPARMOR +IMA +SMACK +SECCOMP +GCRYPT -GNUTLS +OPENSSL +ACL +BLKID +CURL +ELFUTILS +FIDO2 +IDN2 -IDN +IPTC +KMOD +LIBCRYPTSETUP +LIBFDISK +PCRE2 -PWQUALITY +P11KIT +QRENCODE +TPM2 +BZIP2 +LZ4 +XZ +ZLIB +ZSTD -BPF_FRAMEWORK -XKBCOMMON +UTMP +SYSVINIT default-hierarchy=unified Here is my testcase for a user-level service illustrating my problem: Create a file /tmp/test.sh with the following contents: ------------------------- test.sh ------------------------- while :; do echo ritzelbimpf echo ritzelbimpf | logger echo ritzelbimpf | systemd-cat echo foobarbaz echo foobarbaz | logger echo foobarbaz | systemd-cat sleep 10 done ------------------------- test.sh ------------------------- Create a user-level service in file ~/.config/systemd/user/test.service with the following contents: ------------------------- test.service ------------------------- [Unit] Description=test service [Service] ExecStart=/bin/bash /tmp/test.sh LogFilterPatterns=~ritzelbimpf ------------------------- test.service ------------------------- Then execute: [~]$ systemctl --user daemon-reload [~]$ systemctl --user start test.service [~]$ systemctl --user stop test.service This results in the following messages in the journal for me: ------------------------- test.service ------------------------- Jan 12 14:36:30 host01 systemd[1377]: Reloading... Jan 12 14:36:30 host01 systemd[1377]: Reloading finished in 69 ms. Jan 12 14:36:37 host01 systemd[1377]: Started test.service - test service. Jan 12 14:36:37 host01 bash[3372]: ritzelbimpf Jan 12 14:36:38 host01 farblos[3374]: ritzelbimpf Jan 12 14:36:38 host01 cat[3376]: ritzelbimpf Jan 12 14:36:38 host01 bash[3372]: foobarbaz Jan 12 14:36:38 host01 farblos[3379]: foobarbaz Jan 12 14:36:38 host01 cat[3381]: foobarbaz Jan 12 14:36:45 host01 systemd[1377]: Stopping test.service - test service... Jan 12 14:36:45 host01 systemd[1377]: Stopped test.service - test service. ------------------------- test.service ------------------------- That is, these "ritzelbimpf" messages come through unfiltered. What am I missing here? And: If my approach is fundamentally flawed, how would a minimal test case for a user-level service look like that demonstrates how/that LogFilterPatterns= works?