Dell EMC Unity: Writing to /tmp on Unity system will cause an SP Reboot if /tmp becomes full
Summary: Writing to /tmp on Unity system will cause an SP Reboot if /tmp becomes full. For Unity, /tmp is only 56M in size.
This article applies to
This article does not apply to
This article is not tied to any specific product.
Not all product versions are identified in this article.
Instructions
ISSUE
Writing to /tmp on Unity system will cause an SP Reboot if /tmp becomes full.
In Dell EMC Unity, /tmp is only 56M in size. So saving / copying / moving files to /tmp is not recommended.
CAUSE
This is working as designed.
In Unity, the /tmp file system is only used by the system for generating temporary status files which HA (for example) picks up to determine if the system is up.
If /tmp is full, these status files cannot be created, and HA determines that the system may be in a bad state. It then initiates a graceful reboot in an attempt to resolve this condition.
Since /tmp is a memory drive, it is cleared on reboot.
WORKAROUND
If you need to save or copy files or logs somewhere, use /cores/service since it has more space and is also the user "service" home dir (/cores/service = /home/service)
Additional Information
Please do NOT use /var/tmp directory to save any files either. Though this directory has much more space than /tmp, repeated use may still cause issue and this directory doesn't clear itself after reboot.
service@(none) spb:~> df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/eroot 11G 5.5G 4.8G 54% /
udev 744M 8.0K 744M 1% /dev
tmpfs 2.4G 204M 2.2G 9% /dev/shm
tmpfs 2.4G 239M 2.2G 10% /run
tmpfs 2.4G 0 2.4G 0% /sys/fs/cgroup
/dev/ram0 59M 2.2M 56M 4% /tmp <<<<<<< DON'T use this
/dev/sda1 117M 5.7M 105M 6% /mnt/c4lx-cfg_msata
/dev/sda7 7.9G 1015M 6.5G 14% /cores <<<<<<< Use this
/pramfs 122M 38M 85M 31% /pramfs
/dev/mirrora5 15G 1.1G 13G 8% /EMC/backend/service
/dev/c4nasdba2 3.5G 372M 3.0G 11% /EMC/backend/CEM
/dev/c4nasdba1 1013M 57M 905M 6% /nbsnas
/dev/c4loga2 4.7G 139M 4.3G 4% /EMC/backend/perf_stats
/dev/c4loga1 3.4G 95M 3.1G 3% /EMC/backend/log_shared
/dev/metricsluna1 16G 1.5G 14G 10% /EMC/backend/metricsluna1
/dev/c4fastvpa1 6.0G 144M 5.6G 3% /EMC/fastvp
10:17:08 service@(none) spb:~> pwd
/home/service
10:21:45 service@(none) spb:~> ll -h
total 208K
-rw-r--r-- 1 root root 44K Jun 23 11:07 svc_networkcheck.log
-rw-r--r-- 1 root root 164K Jun 23 11:07 svc_storagecheck.log
10:21:54 service@(none) spb:~> cd /cores/service
10:22:04 service@(none) spb:/cores/service> ll -h
total 208K
-rw-r--r-- 1 root root 44K Jun 23 11:07 svc_networkcheck.log
-rw-r--r-- 1 root root 164K Jun 23 11:07 svc_storagecheck.log
10:23:23 service@(none) spb:/cores/service> ll -h /home/service
lrwxrwxrwx 1 root root 14 May 10 09:14 /home/service -> /cores/service
service@(none) spb:~> df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/eroot 11G 5.5G 4.8G 54% /
udev 744M 8.0K 744M 1% /dev
tmpfs 2.4G 204M 2.2G 9% /dev/shm
tmpfs 2.4G 239M 2.2G 10% /run
tmpfs 2.4G 0 2.4G 0% /sys/fs/cgroup
/dev/ram0 59M 2.2M 56M 4% /tmp <<<<<<< DON'T use this
/dev/sda1 117M 5.7M 105M 6% /mnt/c4lx-cfg_msata
/dev/sda7 7.9G 1015M 6.5G 14% /cores <<<<<<< Use this
/pramfs 122M 38M 85M 31% /pramfs
/dev/mirrora5 15G 1.1G 13G 8% /EMC/backend/service
/dev/c4nasdba2 3.5G 372M 3.0G 11% /EMC/backend/CEM
/dev/c4nasdba1 1013M 57M 905M 6% /nbsnas
/dev/c4loga2 4.7G 139M 4.3G 4% /EMC/backend/perf_stats
/dev/c4loga1 3.4G 95M 3.1G 3% /EMC/backend/log_shared
/dev/metricsluna1 16G 1.5G 14G 10% /EMC/backend/metricsluna1
/dev/c4fastvpa1 6.0G 144M 5.6G 3% /EMC/fastvp
10:17:08 service@(none) spb:~> pwd
/home/service
10:21:45 service@(none) spb:~> ll -h
total 208K
-rw-r--r-- 1 root root 44K Jun 23 11:07 svc_networkcheck.log
-rw-r--r-- 1 root root 164K Jun 23 11:07 svc_storagecheck.log
10:21:54 service@(none) spb:~> cd /cores/service
10:22:04 service@(none) spb:/cores/service> ll -h
total 208K
-rw-r--r-- 1 root root 44K Jun 23 11:07 svc_networkcheck.log
-rw-r--r-- 1 root root 164K Jun 23 11:07 svc_storagecheck.log
10:23:23 service@(none) spb:/cores/service> ll -h /home/service
lrwxrwxrwx 1 root root 14 May 10 09:14 /home/service -> /cores/service
Affected Products
Dell Unity 300, Dell EMC Unity 400, Dell EMC Unity 400F, Dell EMC Unity 500, Dell EMC Unity 500F, Dell EMC Unity 600, Dell EMC Unity 600F, Dell EMC Unity Family |Dell EMC Unity All Flash, Dell EMC Unity FamilyProducts
Dell EMC Unity Hybrid, Dell EMC UnityVSA Professional Edition/Unity Cloud EditionArticle Properties
Article Number: 000022433
Article Type: How To
Last Modified: 12 Aug 2025
Version: 6
Find answers to your questions from other Dell users
Support Services
Check if your device is covered by Support Services.