编辑：当我尝试使用具有ANY挂载点的单独分区时,会发生这种情况,而不仅仅是/ var.
我正在使用Buildroot来构建嵌入式Linux系统.我正在尝试为/ var使用单独的分区,但这适用于任何挂载点.我的init系统是systemd,udev用于设备管理.我把我的fstab编辑为：
# <file system> <mount pt> <type> <options> <dump> <pass> /dev/root / ext2 rw,noauto 0 1 /dev/mmcblk0p4 /var ext2 defaults 0 2 proc /proc proc defaults 0 0 devpts /dev/pts devpts defaults,gid=5,mode=620 0 0 tmpfs /dev/shm tmpfs mode=0777 0 0 tmpfs /tmp tmpfs defaults 0 0 sysfs /sys sysfs defaults 0 0 tmpfs /run tmpfs defaults 0 0
一旦系统启动,我收到一条消息“Expecting device dev-mmcblk0p4.device …”,最后接着是：
“等待设备dev-mmcblk0p4.device超时.”
“/ var的依赖失败”
“本地文件系统的依赖性失败.”
如果我使用/ var2或其他任何东西作为挂载点而不是/ var,也会发生同样的事情.一旦启动失败,它就进入紧急模式,然后安装将成功发生.然后,我可以退出系统维护,一切都按预期工作.是什么导致了这种延迟安装？我错过了一步吗？
输出屏幕截图：
解决方法
我在这里使用systemd-208与内核3.13.1和3.14.4在Exherbo(类似于Gentoo)下有类似的问题：我的单独分区(/ var,/ home,/ boot和even / swap)安装在所需的根目录下地点.一切都很好.然后,升级到systemd 213,启动进程在该位置停止,其中分区应该已经安装了消息：’启动作业正在运行dev-sdxx.device’,直到超时1分30秒.之后我处于紧急模式.
摘录
摘录
$journalctl -xb Jun 09 13:50:29 exathlon systemd[1]: Job dev-disk-by\x2dlabel-BAK_A4.device/start timed out. Jun 09 13:50:29 exathlon systemd[1]: Timed out waiting for device dev-disk-by\x2dlabel-BAK_A4.device. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /mnt/BAK_A4. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for Local File Systems. Jun 09 13:50:29 exathlon systemd[1]: Triggering OnFailure= dependencies of local-fs.target. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /export/LinuxMint13_KDE_64. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /export/SystemRescueCD-x86. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for File System Check on /dev/disk/by-label/BAK_A4. Jun 09 13:50:29 exathlon systemd[1]: Job dev-sdb11.device/start timed out. Jun 09 13:50:29 exathlon systemd[1]: Timed out waiting for device dev-sdb11.device. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /var. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for Update UTMP about System Boot/Shutdown. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for Load/Save Random Seed. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for File System Check on /dev/sdb11. Jun 09 13:50:29 exathlon systemd[1]: Job dev-sdb8.device/start timed out. Jun 09 13:50:29 exathlon systemd-journal[1044]: Forwarding to syslog missed 15 messages. Jun 09 13:50:29 exathlon systemd[1]: Timed out waiting for device dev-sdb8.device. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /home. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for File System Check on /dev/sdb8. Jun 09 13:50:29 exathlon systemd[1]: Job dev-sda6.device/start timed out. Jun 09 13:50:29 exathlon systemd[1]: Timed out waiting for device dev-sda6.device. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /boot. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for File System Check on /dev/sda6. Jun 09 13:50:29 exathlon systemd[1]: Job dev-sdb5.device/start timed out. Jun 09 13:50:29 exathlon systemd[1]: Timed out waiting for device dev-sdb5.device. Jun 09 13:50:29 exathlon systemd[1]: Dependency Failed for /dev/sdb5.
显示systemd安装失败的尝试.
在查找互联网后,我能够找到配置内核的补救措施
CONFIG_FHANDLE=y (before: n)
请参阅“systemd System and Service Manager”
REQUIREMENTS: CONFIG_FHANDLE (libudev,mount and bind mount handling)
来源：http://cgit.freedesktop.org/systemd/systemd/tree/README
之后问题解决了,所有分区再次安装.
我不知道为什么这不会发生/或者不需要systemd 208.
