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ad4mg
02-20-2010, 02:45 PM
Anybody have any experience with one of these beasts?

http://mysite.verizon.net/ad4mg/N5200.jpg

I'm working on one that has 5 each 1 TB drives in it. No matter which type of RAID array I select, data transfer rates to and from this thing are just slow, barely faster than USB I speeds. I'm testing both the network interface, and the USB interface. Using both 64 bit and a 32 bit machines, trying both Ububtu Linux and Windows XP/Vista.

I'm reformatting the RAID array to "JBOD" now, after fighting the RAID 1 config. Data rates are so slow, playing a multimedia file from the device (WMA, MPEG, FLV, etc) results in the all annoying stop/start/stop playback.

I've already tried RAID 1 and RAID 5, used the device as a USB drive, iSCSI, and a shared resource (after designating a shared folder on the array). Nothing seems to matter much on data transfer rates.

I'll post actual transfer rates shortly, as I have a 166 GB HDD image folder I'm going to copy to the JBOD array.

KC2UGV
02-20-2010, 04:17 PM
Over 100MBit ethernet, no matter the protocol, it's gonna be slower than direct attached SCSI.

It's the reason data centers use fiber to connect SAN (Storage Area Networks) to servers. Even USB is faster than 100MBit ethernet.

kf0rt
02-20-2010, 04:35 PM
Been looking at these, but for the time being, I'm just using a bunch of external USB drives. Works fine and it's cheap(er). Got a RAID controller on this motherboard I'm using, but have it configured for JBOD.

I'm streaming DVD video (converted to AVI) over 54MB WiFi with no hiccups.

ad4mg
02-20-2010, 05:19 PM
Well, ended up going to a RAID 0 array. Copying that HDD image over to it now across the network (100 MBit NIC's, router, and switch). I set the data stripe across the drives at 1024 MB. That set of files (all were maxed at 2 GB at creation time) is moving along at 6.9 MB/sec, according to the dialog box being displayed by Ubuntu. Windows doesn't give transfer speeds on a copy operation, just a "time remaining" estimate.

I am doing a "copy", as opposed to a "move" so as to get an accurate estimate at transfer speeds.

So, I guess a data rate of 6.9 MB/sec is what I should expect?

It's an interesting device ... it runs on Linux, HDD partitions are EXT3, but the shared folder on the RAID array shows up on the network as an NTFS volume.

kf0rt
02-20-2010, 05:43 PM
Awfully slow, but sounds about right for 100Mb Ethernet.

Glad you got it working -- still haven't played with RAID here. Upgraded the main box here to Win 7 some months ago and put in three 1TB drives. All the external stuff is for backup, but it'd be nice to centralize all the data on one NAS device with some fault tolerance. I keep looking for throw-aways at work, but all the "junque" seems to have SCSI drives in the 1-200GB range. Useless.

Switched the home LAN to gigabit a month or two ago because I ran out of ports on the WiFi router (it was the bottleneck). Cost was a $50 DLink switch.

ad4mg
02-20-2010, 08:52 PM
I've acquired a GB router and will test this thing again on a 10/100/1000 network tomorrow. Many online reviews boast transfer speeds of 30-40 MB/sec on a 1GB network. That should be reasonable to expect given that I'm getting 6.9 MB/sec on a 10/100 LAN.

n6hcm
02-21-2010, 04:27 AM
Windows doesn't give transfer speeds on a copy operation, just a "time remaining" estimate.

get robocopy from microsoft--it's free and at the end of each run there's a summary which includes useful stats.