How to find the reason of server load?

Ubuntu server 16.04.1 - after reboot, became available. Found that is loaded into emergency mode "Emergency mode". SSDS - RAID - trying to test booting into "Rescue" - fsck -y /dev/md127 on both drives says that there are no errors. Where to look, what to look for? Please help.

UPD

Checked /etc/fstab - there are some nonsense

# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc noauto,nodev,noexec,nosuid 0 0
# / was on /dev/sda1 during installation
UUID=95f1c169-cdad-486e-a458-4df0be5d3dd4 / ext4 noauto,errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=2cb7074c-95d8-4c66-8e80-45824baee9ed none swap noauto,sw 0 0
/dev/fd0 /media/floppy0 auto noauto,rw,user,exec,utf8 0 0
aufs / aufs rw 0 0
tmpfs /tmp tmpfs nosuid,nodev 0 0</pass></dump></options></type></mount></file>


Perhaps the reason for this? How to fix it?
July 2nd 19 at 13:42
2 answers
July 2nd 19 at 13:44
Solution
The exact cause is not clear. As I can guess, came off RAID(5) there were errors on the second disk sdb

Error miraculously healed, probably by fsck -y /dev/md2
Then restored the RAID, first stopped all the(0,1,2) multi-device mdadm --stop /dev/md0 ...
Then run for luck mdadm --assemble --scan --force - it brought me RAID5 again. It worked, but how dumb it is

~# more /proc/mdstat
Faceted personalities : [raid1] [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid10] 
md1 : active raid5 sdb2[1] sda2[0]
 39028736 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/2] [UU_]

md2 : active raid5 sdb3[1] sda3[0]
 460208128 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/2] [UU_]
 bitmap: 2/2 pages [8KB], 65536KB chunk

md0 : active raid1 sdb1[1] sda1[0]
 291520 blocks super 1.2 [3/2] [UU_]


[3/2] [UU_] - very similar to the error. Support said that I have three disks sda, sdb, sdc, but in the RAID I've only got two disk, and a third for mirroring. Did not understand what he meant...
July 2nd 19 at 13:46
Connect the IP KVM and see what is displayed on the screen

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