RE: Simple HDR question

Posted in 2004

Davis Kwong — Wed, 4 Feb 2004 19:28:26 -0800 — source: Usenet: comp.databases.informix

--0__=08BBE4A2DF808E058f9e8a93df938690918c08BBE4A2DF808E05 Content-type: multipart/alternative; Boundary="1__=08BBE4A2DF808E058f9e8a93df938690918c08BBE4A2DF808E05" --1__=08BBE4A2DF808E058f9e8a93df938690918c08BBE4A2DF808E05 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: quoted-printable Hi After bringing down the primary and then switching the secondary to standard (for updates), then switch the standard back to secondary, the= n bring back up the primary. When the standard switches back to secondary= , the secondary will try to connect to the primary, but since the primary= is offline, that connection will not succeed and the secondary remains as secondary. Later, when the primary is back online as primary, it will connect to the secondary, now the connection succeeds and the 2 servers= determine which one needs failure recovery. Since the secondary (when standard) had additional updates, it is determined that the primary wil= l need failure recovery, so the secondary sends over the newer logfiles t= o the primary. Now the DR pair servers are in sync. thanks. davis. = mosserp@wellsfarg = o.com = = To 02/04/2004 04:06 Davis Kwong/Menlo Park/IBM@IBMUS= PM = cc informix-list@iiug.org, = DirkM@mxgroup.co.za = Subj= ect RE: Simple HDR question = = = = = = = > -----Original Message----- > From: owner-informix-list@iiug.org > [mailto:owner-informix-list@iiug.org] On Behalf Of Davis Kwong > Sent: Wednesday, February 04, 2004 11:46 AM > To: Dirk Moolman > Cc: informix-list@iiug.org; owner-informix-list@iiug.org > Subject: Re: Simple HDR question > > Hi. > > If the HDR pair is up, then the secondary is in read-only > mode. However, if the primary server is down, then the > secondary can switch to operate in a "standard" mode, which > will allow updates. If and when the primary is online again > (as primary server), and the standard (secondary) server is > switch back to a secondary server, then HDR pair will resync > so that updates from the secondary (standard) server will be > applied to the primary server. > > thanks. davis. Huh??? Are you saying that I can now -- bring down the primary; -- switch secondary to standard mode; -- bring the primary back up (it's still in primary mode, remember) -- switch the secondary back to secondary mode (with no physical restor= e??) And then they will sync up and continue merrily on their way?????? Unle= ss HDR has had some BIG changes lately, I don't think that this will work.= It's never worked this way for me. Thanks, Paul Mosser > > "Dirk Moolman" <DirkM@mxgroup.co.za> > << snipped >> = --1__=08BBE4A2DF808E058f9e8a93df938690918c08BBE4A2DF808E05 Content-type: text/html; charset=US-ASCII Content-Disposition: inline Content-transfer-encoding: quoted-printable <html><body> Hi After bringing down the primary and then switching the secondary to sta= ndard (for updates), then switch the standard back to secondary, then b= ring back up the primary. When the standard switches back to secondary,= the secondary will try to connect to the primary, but since the primar= y is offline, that connection will not succeed and the secondary remain= s as secondary. Later, when the primary is back online as primary, it w= ill connect to the secondary, now the connection succeeds and the 2 ser= vers determine which one needs failure recovery. Since the secondary (w= hen standard) had additional updates, it is determined that the primary= will need failure recovery, so the secondary sends over the newer logf= iles to the primary. Now the DR pair servers are in sync. thanks. davis. <img src=3D"cid:10__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" width=3D= "16" height=3D"16" alt=3D"Inactive hide details for mosserp@wellsfargo.= com">mosserp@wellsfargo.com <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= <tr valign=3D"top"><td style=3D"background-image:url(cid:20__=3D08BBE4A= 2DF808E058f9e8a93df938@us.ibm.com); background-repeat: no-repeat; " wid= th=3D"40%"> <ul> <ul> <ul> <ul>mosserp@wellsfargo.com 02/04/2004 04:06 PM</ul> </ul> </ul> </ul> </td><td width=3D"60%"> <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58" alt=3D""> <div align=3D"right">To</div></td><td width=3D"= 100%"><img src=3D"cid:30__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" = border=3D"0" height=3D"1" width=3D"1" alt=3D""> Davis Kwong/Menlo Park/IBM@IBMUS</td></tr> <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58" alt=3D""> <div align=3D"right">cc</div></td><td width=3D"= 100%"><img src=3D"cid:30__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" = border=3D"0" height=3D"1" width=3D"1" alt=3D""> informix-list@iiug.org, DirkM@mxgroup.co.za</td= ></tr> <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D08BBE4A2DF808E058f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58@