Promoting RSS Secondary?
Question: with a primary A and two RSS secondaries B and C, after A fails and B is promoted, is there a way to make C an RSS secondary of B without taking a fresh archive of B and shipping it over the WAN? Art Kagel suggested promoting B from RSS to HDR secondary (even with A down) and then to primary, and noted that if the network is reliable enough it's better to run one of B/C as an asynchronous HDR primary with the other as RSS. The poster preferred RSS due to network reliability issues and speculated that simply promoting C to standard and using 'onmode -d add RSS' on each side might suffice; no definitive confirmation of that approach is recorded in the thread.
Auto-generated by DrWatson from the posts below — may be imperfect; read the full thread.
Consider a cluster with three servers, A, B, & C. Server A is the primary (not HDR primary), and servers B & C are RSS secondaries. Let us say that server A fails, or is otherwise removed from service. I can change one of the secondaries (say B) to standard, and put it in service in place of the original server A. So that's not a problem. But, at the end of the day, I'd like to have B as a primary, and C as an RSS secondary to B. Is there a shorter way to get C to be RSS secondary with B, without having to take a new archive of B and sending it across the WAN to C, etc.? I mean, when A fails, B & C are already the same... (I guess they just don't know it.) Thank you. DG
P.S. I want to use a method very similar to this to bring new servers into production without much down time. That is, I currently have A & B as an RSS primary and secondary, respectively. I want to add C & D as new RSS secondaries. Then remove B from service, leaving A as primary and C & D as RSS secondaries. Then remove A, promote C, and have C & D as permanent RSS primary and secondary. DG
David: Bring B up from RSS to HDR secondary with A as primary (yes, I know A will be down) then from there bring B up to primary mode. It would be better, if your communications are fast and reliable enough, to have one of B or C be HDR primary in asychronous mode and the other as RSS. Art Art S. Kagel, Principal Consultant ASK Database Management Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Thu, Feb 20, 2014 at 11:49 AM, DAVID GROVE <david.grove@alaska.gov>wrote: > Consider a cluster with three servers, A, B, & C. Server A is the primary > (not > HDR primary), and servers B & C are RSS secondaries. Let us say that > server A > fails, or is otherwise removed from service. I can change one of the > secondaries (say B) to standard, and put it in service in place of the > original server A. So that's not a problem. But, at the end of the day, I'd > like to have B as a primary, and C as an RSS secondary to B. > > Is there a shorter way to get C to be RSS secondary with B, without having > to > take a new archive of B and sending it across the WAN to C, etc.? I mean, > when > A fails, B & C are already the same... (I guess they just don't know it.) > > Thank you. > > DG > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --001a11c368586be16704f2d95bf4
Thank you, Art. We have some issues with our network reliability, and we think RSS replication is to be preferred over HDR. This was also the recommendation of a well-known and highly-regarded Informix expert who visited us recently. Regards, DG
I admit bad form in continuing to reply to my own posts.
However... could it be as simple as retiring the original RSS primary,
bringing C (an RSS secondary server) to standard and executing 'onmode -d add
RSS <server D>' on it. Then, on D (what was the other RSS secondary) execute
'onmode -d RSS <server C>' ?
DG
As I said, "if" you communications are reliable... Art Art S. Kagel, Principal Consultant ASK Database Management Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Thu, Feb 20, 2014 at 12:25 PM, DAVID GROVE <david.grove@alaska.gov>wrote: > Thank you, Art. > > We have some issues with our network reliability, and we think RSS > replication > is to be preferred over HDR. This was also the recommendation of a > well-known > and highly-regarded Informix expert who visited us recently. > > Regards, > > DG > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --001a11349a02b304ec04f2da62d7
Absolutely. I didn't intend any implication that you had not so qualified your response. I always appreciate your thoughts, and try to chew on them and extract every nuance possible. Thank you. DG