Disk is full writing

180406 1:13:35 [Warning] Disk is full writing ‘./DATABASE/exp_search.TMD’ (Errcode: 122). Waiting for someone to free space… (Expect up to 60 secs delay for server to continue after freeing disk space)
180406 1:13:35 [Warning] Retry in 60 secs. Message reprinted in 600 secs

Anyone sean this before as far as I am aware the server does not set quota on database.

I have set the user to have unlimited have run the check configuration and check disk quota with no errors.

Disk is not full:

Filesystem Size Used Avail Use% Mounted on
/dev/md2 682G 268G 379G 42% /
udev 10M 0 10M 0% /dev
tmpfs 2.4G 77M 2.3G 4% /run
tmpfs 5.9G 0 5.9G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 5.9G 0 5.9G 0% /sys/fs/cgroup
/dev/md1 488M 58M 405M 13% /boot
tmpfs 1.2G 0 1.2G 0% /run/user/1000

This does freeze the server over and over again, any thoughts?

Check your logs files and try flush them.