系统log 出现 Failed to abandon session scope: Connection timed out 错误, reboot无法重启
解决办法就是让postfix只用IPv4。
打开文件：/etc/postfix/main.cf
inet_protocols = all
修改成
inet_protocols = ipv4
systemd-logind: Failed to start session scope session-1499.scope: Connection timed out
systemctl stop systemd-logind