我的服务器（运行 Centos Stream 版本 8）昨天晚上停止响应 http。我今天早上尝试通过 SSH 进入它，但没有成功，只剩下一个空的挂起的 PuTTy 屏幕。我通过我的网络主机的控制面板（Hetzner）进行了自动重置，几分钟后它就恢复了，一切似乎都正常工作。
我以为是空间不够了，结果确实df显示 /dev/md2 已满 100%（尽管它显示其大小为 9.8G，但实际空间为 9.5G）。我删除了一些东西，将空间减少到 50%。不过，里面没有新文件，我觉得它已经满了一个月或更长时间了……
然后我查看了/var/log/messages最新的报告，发现了以下内容：
Apr 16 18:47:57 originals systemd[1]: Starting dnf makecache...
Apr 16 18:48:28 originals dnf[87659]: CentOS Stream 8 - AppStream 20 kB/s | 4.4 kB 00:00
Apr 16 18:48:28 originals dnf[87659]: CentOS Stream 8 - BaseOS 38 kB/s | 3.9 kB 00:00
Apr 16 18:48:28 originals dnf[87659]: CentOS Stream 8 - Extras 35 kB/s | 2.9 kB 00:00
Apr 16 18:48:28 originals dnf[87659]: CentOS Stream 8 - Extras common packages 19 kB/s | 3.0 kB 00:00
Apr 16 18:48:29 originals dnf[87659]: Extra Packages for Enterprise Linux 8 - x86_64 33 kB/s | 23 kB 00:00
Apr 16 18:48:30 originals dnf[87659]: Extra Packages for Enterprise Linux 8 - Next - 57 kB/s | 25 kB 00:00
Apr 16 18:48:30 originals dnf[87659]: Google Cloud SDK 3.8 kB/s | 1.4 kB 00:00
Apr 16 18:48:31 originals dnf[87659]: nginx mainline repo 160 kB/s | 2.9 kB 00:00
Apr 16 18:48:32 originals dnf[87659]: Metadata cache created.
Apr 16 18:48:32 originals systemd[1]: dnf-makecache.service: Succeeded.
Apr 16 18:48:32 originals systemd[1]: Started dnf makecache.
Apr 16 18:49:28 originals systemd[1]: dev-disk-by\x2duuid.device: Job dev-disk-by\x2duuid.device/start timed out.
Apr 16 18:49:28 originals systemd[1]: Timed out waiting for device dev-disk-by\x2duuid.device.
Apr 16 18:49:28 originals systemd[1]: Dependency failed for /dev/disk/by-uuid.
Apr 16 18:49:28 originals systemd[1]: dev-disk-by\x2duuid.swap: Job dev-disk-by\x2duuid.swap/start failed with result 'dependency'.
Apr 16 18:49:28 originals systemd[1]: dev-disk-by\x2duuid.device: Job dev-disk-by\x2duuid.device/start failed with result 'timeout'.
Apr 16 18:49:28 originals systemd[1]: Timed out waiting for device dev-disk-by\x2duuid.device.
Apr 16 18:49:28 originals systemd[1]: Dependency failed for /dev/disk/by-uuid.
Apr 16 18:49:28 originals systemd[1]: dev-disk-by\x2duuid.swap: Job dev-disk-by\x2duuid.swap/start failed with result 'dependency'.
Apr 16 18:49:28 originals systemd[1]: dev-disk-by\x2duuid.device: Job dev-disk-by\x2duuid.device/start failed with result 'timeout'.
有人能告诉我我可能需要担心什么吗？还是只是因为内存/dev/md2满了，即使内存已经满了一段时间了？还是上面的情况表明我即将出现硬件故障？
编辑：
再次查看messages我发现这些 x2uuid 错误在重启之前和之后都相对频繁地发生，并且可能完全不相关。
答案1
这听起来像是您的 /etc/fstab 中有一个尝试挂载的条目/dev/disk/by-uuid（而不是预期的/dev/disk/by-uuid/SOMETHING）。可能是前缀和粘贴的 UUID 之间有一个空格，或者 fstab 文件中完全缺少 UUID。
运行systemctl status 'dev-disk-by\x2duuid.swap'并记下“Loaded:”行。如果它显示：
Loaded: loaded (/etc/fstab; generated)
那么它肯定来自 /etc/fstab 条目。编辑该文件并修复错误条目。