重启 EC2 实例后，Scylla 无法挂载 RAID 卷

Question

我是 Scylla 的新手。我已经按照 Scylla website 上的安装步骤在我的 AWS 账户中设置了一个小型 4 节点 Scylla 集群。我在我的 EC2 实例上使用 Scylla ami。

如果我停止其中一个 EC2 实例，然后再次启动它。当我尝试重新启动 Scylla 时，我收到消息 Failed mounting RAID volume!。

我相信我必须通过运行以下命令重新安装 RAID 卷：

scylla_raid_setup --raiddev /dev/md0 --disks /dev/nvme1n1,/dev/nvme2n1 --update-fstab --root /var/lib/scylla --volume-role all

但是，当我尝试启动 Scylla 时，我收到以下错误消息：

A dependency job for scylla-server.service failed. See 'journalctl -xe' for details.

好像挂载失败了，日志如下：

-- Subject: Unit var-lib-scylla.mount has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit var-lib-scylla.mount has failed.
--
-- The result is dependency.
Dependency failed for Scylla Server.
-- Subject: Unit scylla-server.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit scylla-server.service has failed.
--
-- The result is dependency.
May 05 13:23:56 systemd[1]: Dependency failed for Scylla JMX.
-- Subject: Unit scylla-jmx.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit scylla-jmx.service has failed.
--
-- The result is dependency.
May 05 13:23:56 systemd[1]: Job scylla-jmx.service/start failed with result 'dependency'.
May 05 13:23:56 systemd[1]: Dependency failed for Run Scylla Housekeeping daily mode.
-- Subject: Unit scylla-housekeeping-daily.timer has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit scylla-housekeeping-daily.timer has failed.
--
-- The result is dependency.
May 05 13:23:56 polkitd[4226]: Unregistered Authentication Agent for unix-process:7668:53288 (system bus name :1.20, object path /org/freedesktop/PolicyKit1/AuthenticationAge
May 05 13:23:56 systemd[1]: Job scylla-housekeeping-daily.timer/start failed with result 'dependency'.
May 05 13:23:56 sudo[7666]: pam_unix(sudo:session): session closed for user root
May 05 13:23:56 systemd[1]: Dependency failed for Run Scylla Housekeeping restart mode.
-- Subject: Unit scylla-housekeeping-restart.timer has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit scylla-housekeeping-restart.timer has failed.
--
-- The result is dependency.
May 05 13:23:56 systemd[1]: Job scylla-housekeeping-restart.timer/start failed with result 'dependency'.
May 05 13:23:56 systemd[1]: Job scylla-server.service/start failed with result 'dependency'.
May 05 13:23:56 systemd[1]: Job var-lib-scylla.mount/start failed with result 'dependency'.
May 05 13:23:56 systemd[1]: Job dev-disk-by\x2duuid-67fde517\x2d892a\x2d4a3f\x2d9e19\x2dac71c9bdd533.device/start failed with result 'timeout'.

我的下一步应该是什么？

这是磁盘：

Disk /dev/nvme1n1: 7500.0 GB, 7500000000000 bytes, 14648437500 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/nvme2n1: 7500.0 GB, 7500000000000 bytes, 14648437500 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/nvme0n1: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000b0301

如果我在 scylla_raid_setup 的磁盘中包含 nvme0n1，那么它会返回：/dev/nvme0n1 is busy。

否则，这就是 scylla_raid_setup 的输出：

Creating RAID0 for scylla using 2 disk(s): /dev/nvme2n1,/dev/nvme1n1
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
meta-data=/dev/md0               isize=512    agcount=32, agsize=114438912 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=3662043136, imaxpct=5
         =                       sunit=256    swidth=512 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=521728, version=2
         =                       sectsz=512   sunit=8 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

我的/etc/fstab 文件如下所示：

UUID=0a84de8e-5bfe-43e7-992b-5bfff8cdce43 /                       xfs     defaults        0 0
UUID="67fde517-892a-4a3f-9e19-ac71c9bdd533" /var/lib/scylla xfs noatime,nofail 0 0
UUID="24aab0fc-dc32-48de-bf6b-5a3d5bcd1f00" /var/lib/scylla xfs noatime,nofail 0 0

我删除了其中一个条目并尝试重新启动 Scylla。但它仍然无法启动:(

运行 systemctl start var-lib-scylla.mount 后：

May 06 14:18:18 ip-172-31-14-126.ec2.internal polkitd[4760]: Registered Authentication Agent for unix-process:7789:57998 (system bus name :1.34 [/usr/bin/pkttyagent --notify-fd 5 --fallback], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_GB.UTF-8)
May 06 14:19:48 ip-172-31-14-126.ec2.internal systemd[1]: Job dev-disk-by\x2duuid-17c356e1\x2d1ec9\x2d47d1\x2d8e98\x2d45182b7a9454.device/start timed out.
May 06 14:19:48 ip-172-31-14-126.ec2.internal systemd[1]: Timed out waiting for device dev-disk-by\x2duuid-17c356e1\x2d1ec9\x2d47d1\x2d8e98\x2d45182b7a9454.device.
-- Subject: Unit dev-disk-by\x2duuid-17c356e1\x2d1ec9\x2d47d1\x2d8e98\x2d45182b7a9454.device has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit dev-disk-by\x2duuid-17c356e1\x2d1ec9\x2d47d1\x2d8e98\x2d45182b7a9454.device has failed.
--
-- The result is timeout.
May 06 14:19:48 ip-172-31-14-126.ec2.internal systemd[1]: Dependency failed for /var/lib/scylla.
-- Subject: Unit var-lib-scylla.mount has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit var-lib-scylla.mount has failed.
--
-- The result is dependency.
May 06 14:19:48 systemd[1]: Job var-lib-scylla.mount/start failed with result 'dependency'.
May 06 14:19:48 systemd[1]: Job dev-disk-by\x2duuid-17c356e1\x2d1ec9\x2d47d1\x2d8e98\x2d45182b7a9454.device/start failed with result 'timeout'.
May 06 14:19:48 polkitd[4760]: Unregistered Authentication Agent for unix-process:7789:57998 (system bus name :1.34, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_GB.UTF-8) (disconnected from bus)
May 06 14:19:48 sudo[7787]: pam_unix(sudo:session): session closed for user root

Answer 1

以下是您可以尝试的步骤

1) 列出所有磁盘

$ fdisk -l

2) 重新创建 RAID

$ sudo /usr/lib/scylla/scylla_raid_setup --disks /dev/nvme2n1,/dev/nvme3n1,/dev/nvme0n1,/dev/nvme1n1…………………<list all the disks you want to create a RAID volume>………………  --raiddev /dev/md0 --update-fstab --root /var/lib/scylla --volume-role all

(Alternative approach)
udevadm settle
mdadm --create --verbose --force --run /dev/md0 --level=0 -c1024 --raid-devices=<NUMBER OF DISKS> /dev/nvme0n1….<SPECIFY THE DISKS COMMA DELIMITED>
udevadm settle

3) 使用 XFS 格式化 raid0 磁盘

$ mkfs.xfs /dev/md0 -f -K

4) 从 fstab 中清除旧条目

$ vi /etc/fstab ## delete the /var/lib/scylla line

5) 将新行添加到 fstab

$ echo "`blkid /dev/md0 | awk '{print $2}'` /var/lib/scylla xfs noatime 0 0" >> /etc/fstab

6) 重新加载守护进程

$ systemctl daemon-reload

7) 挂载文件系统

$ systemctl start var-lib-scylla.mount

8) 重新创建目录

$ mkdir -p "/var/lib/scylla/data"
$ mkdir -p "/var/lib/scylla/commitlog"
$ mkdir -p "/var/lib/scylla/hints"
$ mkdir -p "/var/lib/scylla/coredump"

9) 更改权限

$ chown -R scylla:scylla "/var/lib/scylla"

10) 启动 Scylla

$ systemctl start scylla-server

如果您遇到问题，请告诉我...

Answer 2

您可能应该检查/etc/fstab 的内容，看看您是否有2 个（或更多）scylla 条目（/var/lib/scylla）。如果你这样做了，这可能是挂载失败的原因，应该只有 1 个条目。

如果/etc/fstab中的scylla条目超过1个，或者没有条目，scylla服务将无法启动，这就是您在日志中看到的错误。