Hmmmm. Well shoot, that makes a big difference. That'll teach me to shoot my mouth off without reading the literature closely - I guess I saw the description and backfilled it with my assumption as to how it would work.
I think I prefer the controller based mirroring concept; of course, because the OS is not involved, things like live snapshots of an exchange db aren't feasible with that (although I believe there are some backup products which can do the trick.) Henry > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of Ken > Cornetet > Sent: Friday, June 25, 2004 9:45 AM > To: Exchange Discussions > Subject: RE: Shadow Copying of Exchange 2003 > > > VSS is *not* like mirroring splits at all. > > VSS does not maintain two mirrored copies of the data. Think > of it this > way: Each disk volume has a list of "live" disk blocks. When > a snapshot > is taken, a second list is created of all used disk blocks at that > moment in time. These blocks are then essentially made > read-only. If an > application attempts to write to one of the blocks on the > snapshot list, > the data from that block is copied to an unused block, > modified, and the > "live" block list is updated to point to this new block. Data is never > mirrored. As long as a block remains unchanged, both the snapshot and > live list point to it. The amount of extra disk space > required is solely > a function of how many blocks are updated since the last snapshot, and > how many snapshots are saved. > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On > Behalf Of Henry > Sieff > Sent: Thursday, June 24, 2004 5:00 PM > To: Exchange Discussions > Subject: RE: Shadow Copying of Exchange 2003 > > > Volume shadow copy is like the various volume copying > products used for > years now on high end SAN's (like HDS truecopy/shadowcopy). Basically, > you have two equal sized volumes (PRODUCTION and BACKUP). > These are kept > in sync by the SAN controller. At any time, you can break the > sync, and > then BACKUP is a valid backup of PRODUCTION. You can mount BACKUP on > another server (or the same one if you're not running MSCS) > and use the > file on it or whatever. > > All the syncing is block level, and even if you've had it > unsynced for a > while, its pretty quick to catch up once you unmount and resync. > > Hence the issue (up until now?) with exchange/SQL. While exchange (or > SQL) is running, the files themselves are inconsistant, so > what you had > to do was stop exchange/SQL, then break the pair, then you restart > exchange SQL. Then you could make a tape copy of the BACKUP volume at > your leisure, or not. > > What Volume Shadow Services is supposed to do is handle all of that by > making the files consistant and then syncing then breaking, in effect > giving you an instantaneous backup. > > Henry > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] > Behalf Of Ajay > > > Kulsh > > Sent: Thursday, June 24, 2004 2:32 PM > > To: Exchange Discussions > > Subject: Re: Shadow Copying of Exchange 2003 > > > > > > Ken, > > > > I get the error message "Sorry this meeting has already finished". > > -- > > > > And, about one of my original questions, how can the huge > > exchange database > > of many GBs be copied in "about a minute" and where it is > written to? > > > > So far, only Samantha's response makes sense unless one of > > you have actually > > used this feature and can give some inside info. > > > > Jay > > > > ----- Original Message ----- > > From: Ken Cornetet > > To: Exchange Discussions > > Sent: Thursday, June 24, 2004 8:31 AM > > Subject: RE: Shadow Copying of Exchange 2003 > > > > > > You all may want to view this webcast: > > > > Go to: http://www.placeware.com/cc/mseventsbmo/join > > Your Name: (enter your name) > > Meeting ID: 1032251381 > > Meeting Password: webcast > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of > > Bridges, Samantha > > Sent: Thursday, June 24, 2004 9:57 AM > > To: Exchange Discussions > > Subject: RE: Shadow Copying of Exchange 2003 > > > > > > I understand that you cannot or should not think of Shadow > copying the > > > Exchange IS. The shadow copying feature in Windows 2003 is > for the OS > > > not for a database. To be clearer, you can use shadow copy for > > Windows or the OS not for the Exchange database. > > > > Hope this makes sense. We were in the same thought pattern > as you and > > > learned this wasn't going to work. > > > > Samantha > > > > -----Original Message----- > > From: Ajay Kulsh [mailto:[EMAIL PROTECTED] > > Sent: Wednesday, June 23, 2004 8:42 PM > > To: Exchange Discussions > > Subject: Shadow Copying of Exchange 2003 > > > > > > I need some enlightenment regarding Shadow Copying of Exchange 2003. > > > > I have read MS article - 822896 and some other references to > > understand > > shadow copying. What is not clear to me that if it takes > > typically only > > *about a minute* to create a shadow copy, how long does it > > normally take > > to write this data to a backup hardware? And while backup program is > > writing this, where is data kept? Memory cannot keep so much > > and I don't > > see any hard drive space requirements mentioned. > > > > Can shadow copying of Exchange 2003 only work with backup > > like SAN, not > > normal tape drive? > > > > Jay Kulsh > > > > > > _________________________________________________________________ > > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > > Web Interface: > > http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&t > > ext_mode=& > > lang=english > > To unsubscribe send a blank email to > > %%email.unsub%% > > Exchange List admin: [EMAIL PROTECTED] > > To unsubscribe via postal mail, please contact us at: > > Jupitermedia Corp. > > Attn: Discussion List Management > > 475 Park Avenue South > > New York, NY 10016 > > > > Please include the email address which you have been contacted with. > > > > --- > > [This E-mail scanned for viruses by Declude Virus] > > > > --- > > [This E-mail scanned for viruses by Declude Virus] > > > > > > _________________________________________________________________ > > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > > Web Interface: > > http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&t > ext_mode=& > lang=english > To unsubscribe send a blank email to > %%email.unsub%% > Exchange List admin: [EMAIL PROTECTED] > To unsubscribe via postal mail, please contact us at: > Jupitermedia Corp. > Attn: Discussion List Management > 475 Park Avenue South > New York, NY 10016 > > Please include the email address which you have been contacted with. > > > > _________________________________________________________________ > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > Web Interface: > http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&t ext_mode=& lang =english To unsubscribe send a blank email to %%email.unsub%% Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with. _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&; lang =english To unsubscribe send a blank email to %%email.unsub%% Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with. _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&; lang=english To unsubscribe send a blank email to %%email.unsub%% Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with. _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&lang =english To unsubscribe send a blank email to %%email.unsub%% Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with. _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&lang=english To unsubscribe send a blank email to [EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with.
