現(xiàn)象描述：
一臺(tái)機(jī)器掛載了兩塊數(shù)據(jù)盤(/dev/sdb,/dev/sdc)
[root@localhost ~]# df -h Filesystem ? ? ? ? ? ? ? ? Size Used Avail Use% Mounted on devtmpfs ? ? ? ? ? ? ? ? ? 189M ? ? 0 189M ? 0% /dev tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M ? ? 0 203M ? 0% /dev/shm tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M 628K 203M ? 1% /run tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M ? ? 0 203M ? 0% /sys/fs/cgroup /dev/mapper/openeuler-root ? 17G 8.8G 7.0G 56% / tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M 4.0K 203M ? 1% /tmp /dev/sda1 ? ? ? ? ? ? ? ? ? 976M 120M 790M 14% /boot tmpfs ? ? ? ? ? ? ? ? ? ? ? 41M ? ? 0 ? 41M ? 0% /run/user/989 tmpfs ? ? ? ? ? ? ? ? ? ? ? 41M ? ? 0 ? 41M ? 0% /run/user/0 /dev/sdb ? ? ? ? ? ? ? ? ? 9.8G ? 37M 9.3G ? 1% /test /dev/sdc ? ? ? ? ? ? ? ? ? 9.8G ? 37M 9.3G ? 1% /test1 [root@localhost test1]# ll /test total 24K drwx------ 1 root root ? 4 Dec 5 17:13 nginx drwx------ 2 root root 4.0K Dec 5 17:13 data drwx------ 2 root root 16K Dec 5 16:35 lost+found [root@localhost test1]# ll /test1 total 24K drwx------ 1 root root ? 4 Dec 5 17:13 tomcat drwx------ 2 root root 4.0K Dec 5 17:13 data2 drwx------ 2 root root 16K Dec 5 16:36 lost+found [root@localhost ~]# tail -2 /etc/fstab /dev/sdb /test ext4 ? ? defaults 0 0 /dev/sdc /test1 ext4 ? defaults 0 0
由于掛載的sdb一直沒有使用，數(shù)據(jù)都放在sdc下，所以操作將它刪除，重啟后發(fā)現(xiàn)機(jī)器要一分多鐘才可以連接：查看message日志發(fā)現(xiàn)有timed out：
[root@localhost ~]# cat /var/log/messages |grep -C30 'Timed' Dec 5 17:19:59 localhost kernel: [ ? 56.571447] hv_balloon: Max. dynamic memory size: 1024 MB Dec 5 17:20:40 localhost systemd[1]: dev-sdc.device: Job dev-sdc.device/start timed out. Dec 5 17:20:40 localhost systemd[1]: Timed out waiting for device /dev/sdc. Dec 5 17:20:40 localhost systemd[1]: Dependency failed for /test1. Dec 5 17:20:40 localhost systemd[1]: Dependency failed for Local File Systems. Dec 5 17:20:40 localhost systemd[1]: local-fs.target: Job local-fs.target/start failed with result 'dependency'. Dec 5 17:20:40 localhost systemd[1]: local-fs.target: Triggering OnFailure= dependencies. Dec 5 17:20:40 localhost systemd[1]: local-fs.target: Failed to enqueue OnFailure= job, ignoring: Unit emergency.service has a bad unit file setting. Dec 5 17:20:40 localhost systemd[1]: test1.mount: Job test1.mount/start failed with result 'dependency'. Dec 5 17:20:40 localhost systemd[1]: dev-sdc.device: Job dev-sdc.device/start failed with result 'timeout'. Dec 5 17:20:40 localhost systemd[1]: Starting Restore /run/initramfs on shutdown... Dec 5 17:20:40 localhost systemd[1]: Condition check resulted in Rebuild Dynamic Linker Cache being skipped. Dec 5 17:20:40 localhost systemd[1]: Condition check resulted in Store a System Token in an EFI Variable being skipped. Dec 5 17:20:40 localhost systemd[1]: Condition check resulted in Rebuild Journal Catalog being skipped. Dec 5 17:20:40 localhost systemd[1]: Condition check resulted in Commit a transient machine-id on disk being skipped. Dec 5 17:20:40 localhost systemd[1]: Starting Create Volatile Files and Directories... Dec 5 17:20:40 localhost systemd[1]: Condition check resulted in Update is Completed being skipped.
可能原因：
近期除刪除sdb磁盤外無(wú)其他操作，可能是刪除磁盤導(dǎo)致的
定位思路：
查看磁盤數(shù)據(jù)和盤符是否正常：
[root@localhost ~]# df -h Filesystem ? ? ? ? ? ? ? ? Size Used Avail Use% Mounted on devtmpfs ? ? ? ? ? ? ? ? ? 189M ? ? 0 189M ? 0% /dev tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M ? ? 0 203M ? 0% /dev/shm tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M 632K 203M ? 1% /run tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M ? ? 0 203M ? 0% /sys/fs/cgroup /dev/mapper/openeuler-root ? 17G 8.9G 7.0G 56% / tmpfs ? ? ? ? ? ? ? ? ? ? ? 203M 4.0K 203M ? 1% /tmp /dev/sdb ? ? ? ? ? ? ? ? ? 9.8G ? 37M 9.3G ? 1% /test /dev/sda1 ? ? ? ? ? ? ? ? ? 976M 120M 790M 14% /boot tmpfs ? ? ? ? ? ? ? ? ? ? ? 41M ? ? 0 ? 41M ? 0% /run/user/989 tmpfs ? ? ? ? ? ? ? ? ? ? ? 41M ? ? 0 ? 41M ? 0% /run/user/0 [root@localhost ~]# ll /test total 24K drwx------ 1 root root ? 4 Dec 5 17:13 tomcat drwx------ 2 root root 4.0K Dec 5 17:13 data2 drwx------ 2 root root 16K Dec 5 16:36 lost+found
發(fā)現(xiàn)數(shù)據(jù)沒有丟失，但磁盤名稱和掛載目錄由原來的sdc變成sdb,test1目錄變成test目錄
查看開機(jī)自啟掛載方式：
[root@localhost ~]# tail -2 /etc/fstab /dev/sdb /test ext4 ? defaults 0 0 /dev/sdc /test1 ext4 ? defaults 0 0
確認(rèn)fstab里掛載寫的是磁盤名稱，不是UUID形式，所以當(dāng)刪除無(wú)用數(shù)據(jù)盤sdb后，導(dǎo)致sdc頂替成為了sdb,而文件中本來的sdc由于識(shí)別不到，導(dǎo)致系統(tǒng)重啟Timed out
解決方法：
查看磁盤對(duì)應(yīng)的UUID，更換UUID方式掛載：
[root@localhost ~]# blkid /dev/mapper/openeuler-root: UUID="e45aaa82-334c-4460-a96d-e0f229e1019a" BLOCK_SIZE="4096" TYPE="ext4" /dev/sda2: UUID="VIRBUS-atLc-4Rd6-rsVk-0ZAO-1Gi3-zaCqgZ" TYPE="LVM2_member" PARTUUID="d944d5f4-02" /dev/mapper/openeuler-swap: UUID="3a2e33ca-eda1-473d-aa59-eed4e6e0d533" TYPE="swap" /dev/sdb: UUID="d7770de4-6932-413a-b3ab-5b4e0174dd59" BLOCK_SIZE="4096" TYPE="ext4" /dev/sda1: UUID="541688f6-935c-4ffa-b86b-2c062cbc6c08" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="d944d5f4-01" [root@localhost ~]# sed -i 's#/dev/sdb#UUID=d7770de4-6932-413a-b3ab-5b4e0174dd59#g' /etc/fstab [root@localhost ~]# tail -2 /etc/fstab UUID=d7770de4-6932-413a-b3ab-5b4e0174dd59 /test ext4 ? defaults 0 0 /dev/sdc /test1 ext4 ? defaults 0 0 之后刪除/dev/sdc這行，因?yàn)樗呀?jīng)更名為了/dev/sdb
重啟系統(tǒng)文章來源：http://www.zghlxwxcb.cn/news/detail-439253.html
無(wú)Timed out,搞定~！文章來源地址http://www.zghlxwxcb.cn/news/detail-439253.html
到了這里，關(guān)于解決系統(tǒng)開機(jī)啟動(dòng)緩慢，并提示Timed out waiting for device XXX,Dependency failed for XXX.的文章就介紹完了。如果您還想了解更多內(nèi)容，請(qǐng)?jiān)谟疑辖撬阉鱐OY模板網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章，希望大家以后多多支持TOY模板網(wǎng)！
