I have about 6TB of san disk space used for nightly backups and the management of it is just a pain. For instance if you are using a vendor such as HP for your san disks the compatibility with IBM equipment is not the greatest. We use HP EMA 12000 with hsg80 san storage controllers. TSM will max out the I/O to the san controllers then the particular lun will hang and then the san storage controller must be rebooted to get the lun accessible again to aix but even after the reboot the lun is available to aix but unreadable so now I lost all the data on that lun. I have run into this problem many times over the past few years. HP says disable caching at the controller level which may work but disk I/O will be extremely slow so that is not an option.
You can attribute these problems to incompatible hardware but I would run what ever disk storage you choose through the ringer before you commit to it because I have had this problem with other san storage units as well. We also keep disk storage in multiple locations across campus via long haul san connections which mean multiple luns to manage and many filesystems which if you are in an HACMP configuration takes time for failover to occur and filesystem mounts to take place. In conclusion make sure what ever storage you choose is reliable and able to handle the high I/O load tsm will can on it. -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Paul Zarnowski Sent: Thursday, November 24, 2005 8:40 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: VTS or san disk storage At 11:33 AM 11/23/2005, Dearman, Richard wrote: >We currently use several TB of san based disk storage for our daily >backups which gets migrated during the day to multiple tape libraries. >The san disk administration has become a nightmare [...] I am curious what kind of problems you are running into. At the TSM Symposium at Oxford this year, IBM indicated that they were going to further develop the serial access disk support in TSM. And, TSM 5.3 just added the ability for a SAD devclass to span multiple filesystems. After hearing this, we have been leaning towards investing in inexpensive disk managed by TSM rather than buying a VTL appliance. I'm interested in other's comments about where, specifically, they are having problems managing SAD directly by TSM. ..Paul -- Paul Zarnowski Ph: 607-255-4757 Manager, Storage Systems Fx: 607-255-8521 719 Rhodes Hall, Ithaca, NY 14853-3801 Em: [EMAIL PROTECTED] **************************EMAIL DISCLAIMER*************************** This email and any files transmitted with it may be confidential and are intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient or the individual responsible for delivering the e-mail to the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, is strictly prohibited. If you have received this e-mail in error, please delete it and notify the sender or contact Health Information Management 312.413.4947.
