systemd --user不起作用：
# systemctl --user status
Failed to read server status: Process org.freedesktop.systemd1 exited with status 1
我有：
# echo $XDG_RUNTIME_DIR
/run/user/1000
根本问题似乎是user@1000没有运行。手动启动会产生与登录相同的错误：
# sudo systemctl start user@$(id -u)
Job for [email protected] failed because the service did not take the steps required by its unit configuration.
See "systemctl status [email protected]" and "journalctl -xe" for details.
#systemctl status user@$(id -u)
● [email protected] - User Manager for UID 1000
Loaded: loaded (/usr/lib/systemd/system/[email protected]; static; vendor preset: disabled)
Active: failed (Result: protocol) since Sun 2019-08-18 19:11:41 CEST; 2min 6s ago
Docs: man:[email protected](5)
Process: 13047 ExecStart=/usr/lib/systemd/systemd --user (code=exited, status=1/FAILURE)
Main PID: 13047 (code=exited, status=1/FAILURE)
Tasks: 0
Memory: 452.0K
CGroup: /user.slice/user-1000.slice/[email protected]
Aug 18 19:11:41 arch0713 systemd[1]: Starting User Manager for UID 1000...
Aug 18 19:11:41 arch0713 systemd[13047]: pam_unix(systemd-user:session): session opened for user roland by (uid=0)
Aug 18 19:11:41 arch0713 systemd[13047]: Trying to run as user instance, but $XDG_RUNTIME_DIR is not set.
Aug 18 19:11:41 arch0713 systemd[1]: [email protected]: Failed with result 'protocol'.
Aug 18 19:11:41 arch0713 systemd[1]: Failed to start User Manager for UID 1000.
唯一失败的服务：
# systemctl --failed
UNIT LOAD ACTIVE SUB DESCRIPTION
● [email protected] loaded failed failed User Manager for UID 1000
我还有一些其他的 Arch 安装，其设置基本相同，但问题并不存在。所以我似乎只损坏了这台机器。
重新启动没有帮助。
echo当告诉我已设置$XDG_RUNTIME_DIR 时，我可以检查什么来查找错误的原因？
我不熟悉 systemd 源代码，这当然是一个值得一看的地方，最终我会的，但也许有人给我一个提示。
答案1
我添加了一些额外的日志条目 ( pam_syslog)，journalctl --boot摘录如下。
在pam_systemd.c
453 if (streq_ptr(service, "systemd-user")) {
未输入。之后还会继续。之后的行MYISSUEupdate被执行，但那是在有问题的错误条目之后。
673 r = update_environment(handle, "XDG_RUNTIME_DIR", runtime_path);
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUE
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUEafter
Aug 25 15:49:18 arch0713 kernel: audit: type=1006 audit(1566740958.028:33): pid=424 uid=0 old-auid=4294967295 auid=1000 tty=tty1 old-ses=4294967295 ses=1 res=1
Aug 25 15:49:18 arch0713 systemd-logind[397]: New session 1 of user roland.
Aug 25 15:49:18 arch0713 systemd[1]: Created slice User Slice of UID 1000.
Aug 25 15:49:18 arch0713 systemd[1]: Starting User Runtime Directory /run/user/1000...
Aug 25 15:49:18 arch0713 systemd[1]: Started User Runtime Directory /run/user/1000.
Aug 25 15:49:18 arch0713 audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=user-runtime-dir@1000 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? te>
Aug 25 15:49:18 arch0713 kernel: audit: type=1130 audit(1566740958.058:34): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=user-runtime-dir@1000 comm="systemd" exe="/usr/lib/systemd/sy>
Aug 25 15:49:18 arch0713 systemd[1]: Starting User Manager for UID 1000...
Aug 25 15:49:18 arch0713 systemd[572]: pam_unix(systemd-user:session): session opened for user roland by (uid=0)
Aug 25 15:49:18 arch0713 systemd[572]: Trying to run as user instance, but $XDG_RUNTIME_DIR is not set.
Aug 25 15:49:18 arch0713 kernel: audit: type=1130 audit(1566740958.078:35): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=user@1000 comm="systemd" exe="/usr/lib/systemd/systemd" hostn>
Aug 25 15:49:18 arch0713 audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=user@1000 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res>
Aug 25 15:49:18 arch0713 systemd[573]: pam_unix(systemd-user:session): session closed for user roland
Aug 25 15:49:18 arch0713 systemd[1]: [email protected]: Failed with result 'protocol'.
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUEafter1
Aug 25 15:49:18 arch0713 systemd[1]: Failed to start User Manager for UID 1000.
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUEafter2
Aug 25 15:49:18 arch0713 systemd[1]: Started Session 1 of user roland.
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUEafter3
Aug 25 15:49:18 arch0713 login[424]: pam_systemd(login:session): MYISSUEupdate
然后我发现了这个类似问题。
我比较了
/etc/pam.d/systemd-user
account include system-auth
session include system-auth
auth required pam_deny.so
password required pam_deny.so
我的旧有问题的安装与工作较新的安装。
account include system-login
session required pam_loginuid.so
session include system-login
复制这个就解决了这个问题。看来这并没有被命令改变pacman -Syu。我没有找到太平洋新。