Friday, July 26, 2013

Adding noise to the server room

The last few days have seen me changing my entire IT, not in terms of the system, rather the location. A land line connection needed to be pulled for the phone (skype - land line DECT combi phone), the RED ethernet had to be rewired and finally an ethernet switch was made redundant.

All in all, I am still running the following system:
  • smoothwall express with RED and GREEN connections, running a squid caching proxy
  • my old WiFi-router as an wireless access point (WPA2 of course)
  • the good ole ACER H340 running NAS4Free with a RAIDZ-1 ZFS pool using four 1TB disks, serving as a media server, a file server and a backup server
  • an AMD E-350 system running FreeNAS with a RAID-0 scrap data storage with two 2 TB disks
  • my good ole Buffalo NAS (1TB)
All storage devices are running NFS, SMB and AFP, expect for the Buffalo, which has nof NFS.
To me it is somewhat clear, the H340 is the main, safe, data storage. However, it happened today, one of the 4 HDDs stopped its service. We had a nice warm summer day, temps at about 27 centigrade. The HDDs in the H340 were running at about 50º centigrade, which is somewhat warm.
I shutdown the server, let it sit to cool for some while and fired it up again. The HHD was back, however, some data was potentially written when the HDD took a break. Luckily, I am running a ZFS pool, hence, the disk could be fixed, in ZFS this is called "clear". Everything is back to fine again.

The incident made me rethinking about the H340. There is a post on the internet somewhere, in which someone discloses a mod which changes the H340's case fan.
That seems to be exactly what I need to do, I figured. Indeed, the H340's regulated case fan sucks air out of the case. The fan is arrange such, that air is forced along the HDDs, before exiting the case. Well, that makes some sense :-s Drawing a regulated low amount of hot air along some disk drives...
In my scrap box, there still was this unregulated fan which came with the Antec water cooling used in my workstation. This thing is a real blower, however quite noisy, hence, I did not use it in my workstation PC. However, now that all my servers are in a dedicated noisy room, why not using it in the H340.
This noisy Antec fan is now doing service to blow cool air into the case, over the HHDs, with the following impact, on that same hot summer day (eve):

Temperatures before mod:
  • CPU: 45º C (essentially independent of the ambient temp)
  • HDDs: 47º - 50º C (during idle)
Temperature after mod:
  • CPU:  24º C (essentially the ambient temp)
  • HDDs: 29º - 36º C (during a ZFS pool scrub)
And here is the downside of it. A very quiet device device is now turned into a very noise but well cooled NAS.
Mind you, the H340 is a perfect machine for running NAS4Free! (see earlier post)