ubuntu 16.04 fstab失败，出现nobootwait

我只是干净地安装Ubuntu 16.04（以替换14.04），目的是移植大量工作的fstab文件，以便挂载其他JFS磁盘/分区。但是我似乎遇到麻烦了nobootwait。

例如，在14.04中有效的一个fstab条目是：

UUID=<uuid>  /storage jfs defaults,nodiratime,noatime,nofail,nobootwait  0 2

但是在16.04中，它既不会在启动时挂载驱动器，也不会按照以下命令挂载：

sudo mount /storage

我确实安装了jfsutils，并且能够手动安装分区，即

sudo mount -t jfs /dev/sdX /storage

我发现在 dmesg

[   6.720171] jfs: Unrecognized mount option "nobootwait" or missing value

因此，以此为提示，当我nobootwait从fstab中删除该选项时，该命令

sudo mount /storage 

工作良好。（我不知道在启动时，因为我目前正在通过ssh进行此操作，并且不想冒计算机无法启动的风险）。

显然，一种解决方案是删除该nobootwait选项。但是我不想那样做。也许nobootwait在14.04和14.04中从未起作用（我从未遇到过磁盘启动时故障），只是忽略了该错误，但是我想要的假定功能nobootwait。

在Ubuntu 16.04或linux内核方面是否有所更改nobootwait？

该选项似乎已被删除。Ubuntu的联机帮助的fstab，如果你选择包含本文14.04 LTS顶部：

The  mountall(8)  program  that  mounts  filesystem  during  boot  also
 recognises additional options that the ordinary mount(8) tool does not.
These  are:  ``bootwait''  which  can  be applied to remote filesystems
mounted outside of /usr or /var, without which  mountall(8)  would  not
hold up the boot for these; ``nobootwait'' which can be applied to non-
remote filesystems to explicitly instruct mountall(8) not  to  hold  up
the boot for them; ``optional'' which causes the entry to be ignored if
the filesystem type is not known  at  boot  time;  and  ``showthrough''
which  permits  a mountpoint to be mounted before its parent mountpoint
(this latter should be used carefully, as it can cause boot hangs).

如果在顶部选择16.04，则此版本在您所获得页面的版本中不存在。

如果您只是想nobootwait在16.04中复制行为，似乎您正在寻找的选项是nofail。来自http://manpages.ubuntu.com/manpages/zesty/man5/systemd.mount.5.html

   nofail
       With nofail, this mount will be only wanted, not required, by
       local-fs.target or remote-fs.target. This means that the boot will
       continue even if this mount point is not mounted successfully.

看起来有2个相关选项需要设置以模仿nobootwait行为，该选项取自systemd mount手册页：

   nofail
       With nofail, this mount will be only wanted, not required, by
       local-fs.target or remote-fs.target. This means that the boot will
       continue even if this mount point is not mounted successfully.
   x-systemd.device-timeout=
       Configure how long systemd should wait for a device to show up
       before giving up on an entry from /etc/fstab. Specify a time in
       seconds or explicitly append a unit such as "s", "min", "h", "ms".

因此，将选项设置为nofail,x-systemd.device-timeout=1会使系统在继续引导之前等待1秒钟等待设备安装。

从Ubuntu 16.04开始，默认的初始化系统是systemd，它取代了mountall。 http://manpages.ubuntu.com/manpages/zesty/man5/systemd.mount.5.html提供了可能消除了nobootwait需求的新选项。