On 14 okt. 2011, at 04:09, Prather, Wanda wrote: > Just asking, > I was told that a Protectier doesn't use SHA1 and can't have a hash collision.
I was told that a protectier uses full (bitwise) matching of chunks, so indeed can't have hash collisions because there are none. > Can anybody verify that? > > > -----Original Message----- > From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of > Remco Post > Sent: Wednesday, October 05, 2011 3:15 PM > To: ADSM-L@VM.MARIST.EDU > Subject: Re: [ADSM-L] vtl versus file systems for pirmary pool > > Hi, > > I saw last week that about half of the people visiting the TSM Symposium were > running V6, it's been stable for me so far. > > The likeliness of an accidental SHA1 hash collision is relatively small even > compared to the total number of objects that a TSM server could possibly ever > store during its entire lifetime, insignificant. That being said, if you > think that your data is to valuable to even risk that, don't dedup. > > > -- > > Gr., Remco > > Op 5 okt. 2011 om 19:24 heeft Shawn Drew <shawn.d...@americas.bnpparibas.com> > het volgende geschreven: > >> Along this line, we are still using TSM5.5 Some of the features >> mentioned previously require TSM6. TSM6 still feels risky to me. >> Maybe more risky than a hash collision. >> Just looking for a consensus, Do people think its mature enough now >> that it is as stable/reliable as TSM5 ? >> >> PS. Test restores are the only way to be sure your backups are good. >> You shouldn't just "trust" TSM. >> >> Regards, >> Shawn >> ________________________________________________ >> Shawn Drew >> >> >> >> >> >> Internet >> rrho...@firstenergycorp.com >> >> Sent by: ADSM-L@VM.MARIST.EDU >> 10/05/2011 11:03 AM >> Please respond to >> ADSM-L@VM.MARIST.EDU >> >> >> To >> ADSM-L >> cc >> >> Subject >> Re: [ADSM-L] Ang: Re: [ADSM-L] Ang: Re: [ADSM-L] Ang: Re: [ADSM-L] Ang: >> Re: [ADSM-L] Ang: Re: [ADSM-L] Ang: Re: [ADSM-L] Ang: Re: [ADSM-L] vtl >> versus file systems for pirmary pool >> >> >> >> >> >> >>> When TSM is duplicating your data (aka backing up storage pools), >>> there is no logical connection between your primary storage pool and >>> your copypool. >> >> Well . . .yes . .. no . . . >> >> All our eggs are in one basket no matter what. The logical connection >> between pri and copy pools is TSM itself. A logical corruption in TSM >> can take out both. Your data could be sitting there on tape and >> completely useless. Yes, that's why we have TSM db backups, but are >> they good? What if there is a TSM bug that renders all your backups >> bad - we don't find out until we need it! >> >> At some point you have to trust something. We all trust TSM. Yes, we >> do the db backup, create pri and copy pools, use reuse delay . . >> .everything to allow for problems . . . but we are still trusting that >> TSM workss as advertised. A really, really paranoid would run two >> complete separate/different backup systems - but who can afford that, or >> want to? >> But then, we do do that for our biggest SAP/ORacle systems. We use >> Oracle/RMAN-to-flasharea/RMAN-to-TDPO/TSM, but we also run EMC/clone >> backups off our DR sites R2's . . but also to TSM. >> >> >> Rick >> >> >> >> >> >> ----------------------------------------- >> The information contained in this message is intended only for the >> personal and confidential use of the recipient(s) named above. If the >> reader of this message is not the intended recipient or an agent >> responsible for delivering it to the intended recipient, you are >> hereby notified that you have received this document in error and that >> any review, dissemination, distribution, or copying of this message is >> strictly prohibited. If you have received this communication in error, >> please notify us immediately, and delete the original message. >> >> >> >> This message and any attachments (the "message") is intended solely >> for the addressees and is confidential. If you receive this message in >> error, please delete it and immediately notify the sender. Any use not >> in accord with its purpose, any dissemination or disclosure, either >> whole or partial, is prohibited except formal approval. The internet >> can not guarantee the integrity of this message. BNP PARIBAS (and its >> subsidiaries) shall (will) not therefore be liable for the message if >> modified. Please note that certain functions and services for BNP Paribas >> may be performed by BNP Paribas RCC, Inc. -- Met vriendelijke groeten/Kind Regards, Remco Post r.p...@plcs.nl +31 6 248 21 622
