For the below to work, the book says that the devices have to be directly attached to the HBA's. Has anyone tried configuring alternate path support for SAN attached 3590-H's? The book says that it is not supported.
> A recent version of Atape is required for dual path support. We use > Atape 8.3.1.0. > > You also need to enable alternative pathing support on the rmt device which, > I think is set to off by default: > i.e. chdev -l <device> -a alt_pathing=yes > Then when you make the devices available to the host you will notice > twice the number of drives. If you look at the device attributes with > lsattr -El rmtx > you will notice the location code xx-xx-xx-ALT or PRI , > the primary device value and the WWN. The latter will be 0xnnnnnnnnnn4nnnnn for > the primary device and 0xnnnnnnnnnn8nnnnn for the alternative device. > These allow you to 'pair' up the devices. > > If you have more than 3 or 4 tape devices I would recommend you employ a naming > convention to the devices to make these pairs more transparent, by renaming them > after cfgmgr has brought them into the system. > Thus, we do a rmdev -l <rmtX> ; chdev -l <rmtX> -a new_name=rmtY > such that the secondary / Alternative device name is 50 greater than primary > device name - i.e: > rmt2 => rmt52 > rmt3 => rmt53 and so on. > > Note that errpt will log errors against both device names, depending on which > interface the drive was being accessed when the error occurred. > > Finally, our experience tallies with Steve Harris' - failover is seamless > - we pulled the active cable from a drive while backing up (test !) client > data to tape and the backup carried on over the other path. TSM didn't blink. > We subsequently audited the tape and all was OK. > > Regards > ------------------------------------------------------------------- > Ian Smith > Oxford University Computing Services, Oxford, UK. > ------------------------------------------------------------------- > > > > > > ~>Mime-Version: 1.0 > ~>Content-Transfer-Encoding: quoted-printable > ~>Content-Disposition: inline > ~>Date: Tue, 18 Nov 2003 08:48:41 +1000 > ~>From: Steve Harris <[EMAIL PROTECTED]> > ~>Subject: Re: 2 fibre interfaces per drive > ~>To: [EMAIL PROTECTED] > ~>X-Oxmail-Spam-Status: score=0.0 tests= > ~>X-Oxmail-Spam-Level: > ~> > ~>Joni, > ~> > ~>Later versions of the Atape driver support dual pathing and failover. > ~>Once set up, AIX defines two RMTn drives for each physical drive, one with a > device path ending in -PRI and the other in -ALT. > ~> > ~>As I understand it rudimentary load balancing is done - when the tape is > opened, the least busy path is used. > ~> > ~>Failover is also neat. I was running the tapeutil test command and > deliberately varied off the adapter in use. The io just picked up where it left > off on the other path. > ~> > ~>See the Totalstorage Tape Installation and Users Guide, available from > ftp://service.boulder.ibm.com for details > ~> > ~>Steve Harris > ~>AIX and TSM Admin > ~>Queensland Health, Brisbane Australia > ~> > ~>>>> [EMAIL PROTECTED] 18/11/2003 7:13:13 >>> > ~>IBM 3590 and 3592 drives have 2 fibre interfaces. I am unsure how to > ~>manage the multipathing yet, but we are going to look at configuring our > ~>3590H drives that way next year to eliminate that single point of > ~>failure. Our TSM server is running AIX 5.2ML2 which is connected to a > ~>3494 library with 4 3590H drives which are connected to a Brocade 2800. > ~> > ~> > ~>Julian Armendariz > ~>System Engineer - UNIX > ~>H.B. Fuller > ~>(651) 236-4043 > ~> > ~> > ~> > ~>>>> [EMAIL PROTECTED] 11/17/03 12:48PM >>> > ~>Hi everyone! > ~> > ~>We are in the process of formulating an AIX environment instead of our > ~>current MVS TSM environment. We would have 2 TSM servers (one being > ~>the > ~>library manager) with 2 directors, 8 lan-free clients and 24 tape > ~>drives, > ~>which we hope to share between the 2 TSM servers. We would like to > ~>have 2 > ~>fibre interfaces per drive in order to eliminate a single point of > ~>failure. > ~>My question is, how does TSM know which path it is using to the drive > ~>and > ~>how does it know that one of the paths to an individual drive is > ~>already in > ~>use? Is there software out there to manage this or is it done through > ~>the > ~>hardware configuration? If anyone has any suggestions I would > ~>appreciate > ~>it! Thanks! > ~> > ~> > ~>*************************************************************** > ~>Joni Moyer > ~>Highmark > ~>Storage Systems > ~>Work:(717)302-6603 **New as of 11/1/03 > ~>Fax:(717)302-5974 > ~>[EMAIL PROTECTED] > ~>*************************************************************** > ~> > ~> > ~> > ~>****************************************************************************** > ***** > ~>This email, including any attachments sent with it, is confidential and for > the sole use of the intended recipients(s). This confidentiality is not waived > or lost, if you receive it and you are not the intended recipient(s), or if it > is transmitted/received in error. > ~> > ~>Any unauthorised use, alteration, disclosure, distribution or review of this > email is prohibited. It may be subject to a statutory duty of confidentiality > if it relates to health service matters. > ~> > ~>If you are not the intended recipients(s), or if you have received this e-mail > in error, you are asked to immediately notify the sender by telephone or by > return e-mail. You should also delete this e-mail message and destroy any hard > copies produced. > ~>****************************************************************************** > ***** > > Steve Roder, University at Buffalo HOD Service Coordinator VM Systems Programmer UNIX Systems Administrator (Solaris and AIX) TSM/ADSM Administrator UB DNS Team ([EMAIL PROTECTED] | (716)645-3564)
