We moved to virtual tape a long time ago. When projecting costs, you should consider the savings in not having to deal with physical tapes. Just the real estate alone occupied by thousands of tapes is significant, not to mention the labor costs.
. . J.O.Skip Robinson Southern California Edison Company Electric Dragon Team Paddler SHARE MVS Program Co-Manager 323-715-0595 Mobile 626-543-6132 Office ⇐=== NEW [email protected] -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of R.S. Sent: Thursday, January 30, 2020 4:04 AM To: [email protected] Subject: (External):Re: 3592-E07 To complement and clarify: when using physical tapes (* see below) your RPO and RTO may be 36 hours or zero. The advantage of TS7700 is replication feature. However for physical drives in ATL you have to have two libraries in two locations. However you can write to both libraries simultaneously. It requires HSM, DSS or FDR, however for backup purposes it is no problem. More: for some TS7700 (or Oracle VSM) modes of replication your backup on tape maybe replicated asynchronously, with delays of minutes, tens of minutes, etc. For real tape duplexing both copies are closed at the same time of job fails. (*) Physical tape - tape visible to z/OS as a device (via controller as always). Virtual tape - emulated tape drive is visible to z/OS as a device. -- Radoslaw Skorupka Lodz, Poland W dniu 23.01.2020 o 07:31, Timothy Sipples pisze: > Dean Nai wrote: >> Currently we backup everything on 3592 nightly and the next >> morning they go off site for DR purposes, circa 1980’s > OK, so my guess was a good one then. :-) > > So right now your "Recovery Point Objective" (RPO) is circa 36 hours, > probably higher. For example, if you start your backup at 10:00 p.m., the > tapes physically leave at 9:00 a.m., they arrive at your DR site at 10:00 > a.m., and then the next batch arrives every day thereafter at 10:00 a.m., > that's your 36 hours. If, organizationally, your 36 hour RPO is known, > documented, agreed, accepted, and periodically reviewed, great. Then your > goal is simply to get the best (lowest) RPO you can within the minimum > required budgetary and other limits that at least meet the 36 hour RPO. > Basically, you should be free and welcome to exceed the required 36 hour > RPO as long as you don't spend any extra taxpayer dollars to exceed it. :-) > > If the current 36 hour RPO isn't acceptable, different story. It doesn't > seem like RPO=36h would be or should be acceptable, but let's assume for > now it's acceptable. > > I'd like to comment first on some ideas Rex raises: > > Rex Pommier wrote: >> Since it's leased, I don't know if this would even be feasible: >> sticking with the 3592-C07 controller but going to third party >> maintenance. IDK how long parts will be available for them. > It's a fair question to research, as a contingency anyway. The DR site > operator may have a point of view, of course. > >> Will IBM offer some kind of extended (read: for an extra fee) >> support for the C07 controllers? That'll depend on parts availability >> as well. We got it for our C06s while we were migrating off the >> local physical tape. > Also a fair question to research, as a contingency. > > Another contingency possibility to research is "stockpiling." For example, > if you have one 3592-C07 controller per site, install a second one per site > (two more), procured from the secondary market. If one breaks and isn't > repairable, the other hopefully still works. I don't recommend this, and > it's not really a long-term solution. > >> Installing a small VTS at your primary site, and swinging the >> (presumably) 3584 library behind the VTS. The VTS would then become >> in essence a large cache for the tape library. This is one of the >> options we looked at when our 3592-C06 controllers fell off maintenance >> - because we couldn't find and C07s to replace them with. > Yes, the direct replacement is a "smart" controller, which is so smart it > isn't obligatory to equip it with physical tape libraries and tape drives. > Currently that's the IBM TS7770, which became generally available on > November 22, 2019. The TS7770 optionally, currently supports IBM TS1120 > through TS1150 tape drives, depending on which suitably configured tape > library you have (TS3500 or TS4500). When attached to physical tape > libraries/drives it's known as the "TS7770T." The TS7760 is also currently > available. > > I understand Dean has some concerns about direct replacement economics, > though. If the data volumes are quite low, then he could be right. > >> We ended up installing a larger VTS at the local site and a smaller >> one at our secondary location, replicating between them, but we did >> put a 3584 library on the back end of the remote one so we still have >> data going to tape for long term archival. > Yes, that's quite common. > > If we consider Dean's current DR strategy mostly in isolation, and meeting > or beating the current RPO, I'd like to nominate some possible parsimonious > options, in no particular order and often combinable: > > 1. Use a combination of nearline disk (rather than virtual or physical > tape) as your backup target, SafeGuarded Copy (a feature available in IBM > DS8880 and DS8890 storage units), and Global Mirror. This IBM redbook > describes SafeGuarded Copy: > > http://www.redbooks.ibm.com/redpapers/pdfs/redp5506.pdf > > The primary considerations are whether you already have the storage (or > plan to this year) and whether you have the right network connectivity to > your DR site to support Global Mirror (versus the current "tape pickup > truck" connectivity). > > 2. Use cloud object storage along the lines I suggested. Your backup target > and recovery source are the public cloud (such as IBM Cloud Object > Storage), and you simply add the right software to z/OS to use cloud object > storage as if it were (virtual) tape, such as IBM Cloud Tape Connector for > z/OS.(*) As long as at least one cloud object storage pool with a good > backup is adequately reachable from the DR site when you need to recover, > and provided you have a minimum emergency z/OS image (including the cloud > object storage enabling software) for quick IPL from emergency media (DVD > with older HMCs, or USB media on newer) if you need it, you can restore > from the cloud backup to the last good backup point. > > There are some variations, such as contracting with two cloud object > storage providers and running backups to both (just in case one is offline, > somebody forgot to renew the contract, or whatever), using one public > provider and one private provider (whatever your larger organization has > for cloud object storage, and they likely have something already), using > cloud object storage that your DR site operator provides as one of the > pools, and so forth. > > 3. Place one IBM TS7770 -- it could be without physical tape libraries and > tape drives -- at your DR site, and run your backups to that remote virtual > tape library. That gets your backup data off site right away. This too > requires sufficient network connectivity to your DR site, although it isn't > quite as demanding as Global Mirror. > > There are some variations here, too. For example, some shops effectively > run a third "data vault" site. They place one TS7770 across campus in a > completely different building, with no machine or disk, and that's the > "arms length backup vault." They place another TS7770 at the DR site, the > "remote vault." The "arms length" TS7770 then replicates to the "remote" > TS7770. > > (*) I'm aware that Broadcom (CA), Model9, and possibly Compuware > (Innovation Data Processing) also offer software products in this > particular market segment, and there might be others I'm not yet aware of. > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
