Archive for the ‘VTL’ Category

Update

July 13, 2010

It’s been quite some time since I’ve updated this site. It’s been a busy year, both personally and professionally. Since my last update, we have added two Quantum Scalar i2000 libraries. We now have three libraries, one with 48 drives, one with 32 drives, and one with 16 drives. All have LTO-4 drives. We are thinking of upgrading the library with 16 drives to an i6000 with LTO-5 drives and moving the existing 16 drives to the library with 32 LTO-4 drives already. We have upgraded to Networker 7.5.2 still running Solaris 10 on a Sun T2000. We have four Networker Storage Nodes to help back up all the network backup traffic. We now backup about 50 TB per night. Things got so busy on the first Storage Node that we actually were running at 80-90% capacity of a dual-trunked Gigabit Ethernet card. Once this was discovered, we quickly added a third to the trunk and traffic calmed down to 20-30%.

The COPAN VTL was a disaster. We discovered that there was a bug in the software that caused the VTL controller to hang if backup was running at the same time it tried to start the de-duplication. This took COPAN almost a year to fix. Then we discovered that the de-duplicated area was almost impossible to read from. We were trying to restore a 300 GB file and the restore was running at 2-5 MB/s. As you can figure out, it timed out before it could finish. This took them several more months to fix. Their solution was to provide us with some “always-on” disk for the landing area with some cache for the de-duped data disks. The reconstitution of the data would run until the cache would fill, then the cache would write back to the landing area at about 20 MB/s. This was still not acceptable. Their solution was to charge us to replace the de-duped data disks with their “always-on” disk. I estimated that the cost to replace these disks would have been over a hundred thousand dollars. Needless to say, COPAN never came back with a quote to do this and we de-commissioned the COPAN. It is now serving to hold down some tile in the data center.

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“Enabler type is for a different platform”

September 24, 2008

A few months or so, we finally got around to buying Networker licenses for the two COPAN VTL’s we purchased. We were running on temporary licenses for two jukeboxes. This was caused by the failure of the temporary VTL licenses to work.

Once I entered the licenses codes, an error message popped up, “Enabler type is for a different platform”. We opened a ticket with Networker support and the end result was to load a hotfix, “LGTsc07430”.  Unfortunately, this hotfix was supposed to be for Networker 7.4, but after my objection, EMC admitted it should work just fine for 7.3.3 as well.

Unfortunately, installing this fix also forces you to begin using the infamous “daemon.raw” file instead of the old daemon.log we know and hate/love. I tend to have an open window running a “tail -f” on the daemon.log file. Although you can get the gist of the file by reading it, you need an editor to read it properly. Still, I run a tail on the daemon.raw file as well as the daemon.log file (which is still used and needed).

VTL and the KISS principle

May 29, 2008

We are in the process of adding a COPAN VTL to our backup environment. It consists of two FalconStor landing areas with about 13 TB each. Behind them are two COPAN MAID SIR disk trays with about 60 TB each. Each VTL should have about 500 MB/s throughput from the SAN. Unfortunately, we are seeing about 400 MB/s on one and 300 MB/s on the other. As of yet, we do not know why we are not seeing the full performance. Currently, all but one of the six servers are running 2 GB fiber channel. The faster VTL has the one server running 4 GB fiber channel. Each server has an port on the HBA dedicated to the traffic going to the VTL. The obvious thing to try is to convert all those ports to 4 GB fiber channel.