From b7e8d5af06ee840cc48217ca4629cf28aeeb3c50 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:35:19 +0200 Subject: Adding debian version 252.22-1~deb12u1. Signed-off-by: Daniel Baumann --- debian/README.Debian | 112 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 debian/README.Debian (limited to 'debian/README.Debian') diff --git a/debian/README.Debian b/debian/README.Debian new file mode 100644 index 0000000..11f5e32 --- /dev/null +++ b/debian/README.Debian @@ -0,0 +1,112 @@ +Enabling persistent logging in journald +======================================= + +To enable persistent logging, create /var/log/journal: + + mkdir -p /var/log/journal + systemd-tmpfiles --create --prefix /var/log/journal + +systemd will make the journal files owned by the "systemd-journal" group and +add an ACL for read permissions for users in the "adm" group. +To grant a user read access to the system journal, add them to one of the two +groups. + +This will allow you to look at previous boot logs with e. g. +"journalctl -b -1". + +If you enable persistent logging, consider uninstalling rsyslog or any other +system-log-daemon, to avoid logging everything twice. + +Debugging boot/shutdown problems +================================ + +The "debug-shell" service starts a root shell on VT 9 which is available very +early during boot and very late during shutdown. You can temporarily enable +this when booting the system does not get sufficiently far to get a desktop or +even the text console logins (getty), or when shutdown hangs eternally. + +For boot problems the recommended way is to append "systemd.debug-shell" to the +kernel command line in the bootloader. +For shutdown problems, run "systemctl start debug-shell" as root, then shut +down. + +WARNING: Please avoid "systemctl enable debug-shell" as this will start the +debug shell permanently which is a SECURITY HOLE as it allows unauthenticated +and unrestricted root access to your computer if you forget to disable it! +Please only enable it if you cannot pass "systemd.debug-shell" to the boot +loader for some reason, and then immediately run "systemctl disable debug-shell" +after booting. + +Once the boot/shutdown problem happened, switch to VT9 (Ctrl+Alt+F9). There you +can use the usual systemctl or journalctl commands, or any other Linux shell +command to list or kill processes. For example, run "systemctl list-jobs" to +see what's currently being run, or "systemctl" to find units which are not in +the expected state (e. g. "failed" for boot or still "active" during shutdown), +and then get more detailed information with "systemctl status -l foo.service" +to get a service "foo"'s status and recent logging. + +In situations where the debug shell is not available, you can generate a +/shutdown-log.txt file instead: +1. Boot with these kernel command line options: + systemd.log_level=debug systemd.log_target=kmsg log_buf_len=1M +2. Save the following script as /lib/systemd/system-shutdown/debug.sh and make it executable: + #!/bin/sh + mount -o remount,rw / + dmesg > /shutdown-log.txt + mount -o remount,ro / +3. Reboot + +Enable and use networkd +======================= +networkd is a small and lean service to configure network interfaces, designed +mostly for server use cases in a world with hotplugged and virtualized +networking. Its configuration is similar in spirit and abstraction level to +ifupdown, but you don't need any extra packages to configure bridges, bonds, +vlan etc. It is not very suitable for managing WLANs yet; NetworkManager is +still much more appropriate for such Desktop use cases. + +networkd is not enabled by default; run + + systemctl enable systemd-networkd + +if you want to use it. After that you need to create some *.network +configuration files. In the simplest case you just want to run DHCP on all +available Ethernet interfaces: + +--- /etc/systemd/network/all-eth.network --- +[Match] +Name=e* +[Network] +DHCP=yes + +This will match on both the kernel "ethN" as well as the predictable interface +names "en*". Please see man systemd.network(5) for all available configuration +options and examples. + +You need to make sure that interfaces handled by networkd are not handled by +ifupdown (/etc/network/interfaces) and NetworkManager. + +Note that interfaces brought up/down will *not* run hooks in +/etc/network/if-*.d/. + +It is recommended to use networkd together with systemd-resolved(8) to +dynamically manage /etc/resolv.conf: + + systemctl enable systemd-resolved + ln -sf /run/systemd/resolve/resolv.conf /etc/resolv.conf + +Debian's networkd has been modified to also work with the resolvconf package. + +KillUserProcesses behavior in Debian +==================================== + +If KillUserProcesses=yes is configured in logind.conf(5), the session scope +will be terminated when the user logs out of that session. + +See logind.conf(5): + +| Note that setting KillUserProcesses=yes will break tools like screen(1) and +| tmux(1), unless they are moved out of the session scope. + +The default for KillUserProcesses in /etc/systemd/logind.conf is set +to "yes" in upstream systemd, though Debian defaults to "no" (see #825394). -- cgit v1.2.3