| |
|
RSS Feed - WebSphere MQ Support
|
RSS Feed - Message Broker Support
|
| Partial Repository Communications |
« View previous topic :: View next topic » |
| Author |
Message
|
| jefflowrey |
 Posted: Mon Feb 04, 2008 3:09 pm Post subject: |
 |
|
Grand Poobah
Joined: 16 Oct 2002
Posts: 19981
|
| PeterPotkay wrote: |
| Put a cluster on each side and connect them to each other (P2P) with Highly Available Gateways on each side. |
Or a very small overlapped cluster that also overlaps the firewall boundary.
Two qmgrs on each side of the firewall.
And a careful set of qaliases to manage the routing.
_________________
I am *not* the model of the modern major general. |
|
| Back to top |
|
 |
| kkumar_70 |
| Posted: Mon Feb 04, 2008 3:25 pm Post subject: |
|
|
Novice
Joined: 04 Feb 2008
Posts: 10
|
Peter/Jeff,
Appreciate your comments. However, i think you are trying to resolve a problem and/or reason out how to make sure the issues presented on the client site can be resolved.
But that is NOT the contention of this thread as i mentioned earlier. The question that i have been unable to answer myself and trying to undestand is Why does Clustering do a P2P under the covers and how does it differ from a normal P2P setup.
I do understand the various naunces of MQ & Clustering and what is available to us and what is not and how to potentially design/architect such environments.
You know how at times you have something stuck in your mind and it doesn't get out. Similarly, i have this thing stuck in my mind as to why should Clustering do a P2P when ideally it should be flowing everything through the FR.
Another example to this same thread was debugging issues between PR* would be a mess. Did the message actually go through PR->PR route or did it go through PR->FR->PR route? Since channels are available on both routes, debugging issues would be really painful. Wouldn't it?
KK |
|
| Back to top |
|
|
| PeterPotkay |
| Posted: Mon Feb 04, 2008 3:30 pm Post subject: |
|
|
Poobah
Joined: 15 May 2001
Posts: 7722
|
| kkumar_70 wrote: |
Similarly, i have this thing stuck in my mind as to why should Clustering do a P2P when ideally it should be flowing everything through the FR.
|
Sorry, but that comment is illogical in the context of MQ clustering. In a cluster of dozens of QMs you want it designed to all route thru one QM? To be a potential performance bottle neck? To be a single point of failure?
If thats what you want don't use MQ clustering and set up a classic Hub and Spoke architecture.
_________________
Peter Potkay
Keep Calm and MQ On |
|
| Back to top |
|
|
| kkumar_70 |
| Posted: Mon Feb 04, 2008 3:38 pm Post subject: |
|
|
Novice
Joined: 04 Feb 2008
Posts: 10
|
| PeterPotkay wrote: |
| kkumar_70 wrote: |
Similarly, i have this thing stuck in my mind as to why should Clustering do a P2P when ideally it should be flowing everything through the FR.
|
Sorry, but that comment is illogical in the context of MQ clustering. In a cluster of dozens of QMs you want it designed to all route thru one QM? To be a potential performance bottle neck? To be a single point of failure?
If thats what you want don't use MQ clustering and set up a classic Hub and Spoke architecture. |
Sure. But then if everything is to everything in a Clustering env, it is a P2P in itself. So, i may say i better go with P2P instead of clustering so that i can relieve myself of the "perils of clustering" (you know as long as clustering works it is the best MQ feature and when something breaks in there...well.... ).
I mean if clustering was desinged to be a P2P under the hoods, then architecting solutions that spans organizations is a daunty task that requires features of clustering to be used.
So, it would bring us back to the statement that clustering may be advocated for smaller shops that has all their queue managers within a single network where setups could be created to make maximum out of MQ clustering.
KK |
|
| Back to top |
|
|
| jefflowrey |
| Posted: Mon Feb 04, 2008 4:46 pm Post subject: |
|
|
Grand Poobah
Joined: 16 Oct 2002
Posts: 19981
|
I really don't understand why you're still confused on this.
And I'm sure you're going to take that as some attempt on my part to "defend" MQ. Which, I assure you, it's not. I'm just plain confused by what you are saying.
Clustering works the way it does - because that's how it works. And, because at least to most of us - it doesn't make sense to ship everything through the FR.
You asked where in the documentation it said "this is how clustering works".
I showed you.
You continue to expect things of MQ Clustering that are not there, despite claims of having read the documentation man y times. This is confusing to me.
And, let's be clear on another point.
Architecting solutions that spans organizations is a daunty task.
No matter what you do, you have to a) spend a lot of time thinking about it, b) spend a lot of time designing it, c) take each individual organization into account. And, again, there's nothing in the MQ Cluster docs or any other documentation on the product (at least that I'm aware of) that says that MQ is designed for this kind of massive B2B, or that MQ Clustering is the right choice here either.
There are, certainly, ways you can use MQ or MQ Clustering for this. That doesn't mean there aren't other ways, or that those other ways might not be better for this particular need. Nothing in the documentation, that you say you've read a lot, claims otherwise.
_________________
I am *not* the model of the modern major general. |
|
| Back to top |
|
|
| fjb_saper |
| Posted: Mon Feb 04, 2008 9:38 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
I believe part of the confusion comes from the way clustering works the first time a route is needed.
The first time an unknown route is needed in the PR, the PR queries the FR about the routing information it needs. Upon receiving that information it sets up a P2P communication with its target.
So what you have is PR1->FR->PR1->PR2.
As you may notice there is no PR1->FR->PR2 !
But the actual message travels on a PR1->PR2 path.
The side step to the FR only provides topology information to PR1 and does not transport any message payload like in the PR1->PR2 path...
I hope this cleared up a little and did not confuse more....
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| Vitor |
| Posted: Tue Feb 05, 2008 2:16 am Post subject: |
|
|
Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
|
| kkumar_70 wrote: |
| Sure. But then if everything is to everything in a Clustering env, it is a P2P in itself. So, i may say i better go with P2P instead of clustering so that i can relieve myself of the "perils of clustering" (you know as long as clustering works it is the best MQ feature and when something breaks in there...well.... ). |
My 2 cents,
If you have a site of any size, defining the P2P connections between queue managers is a task of similar complexity to building a cluster. Maintaining those links when queue managers move, IP addresses are changed, etc is much easier with a cluster. Consider a box changing it's IP address - how many definitions need to be changed in a P2P, and how many in a cluster setup?
The "perils of clustering" and "can't find a lost message" is hogwash. As you correctly point out, you have a P2P set up in which the normal problem resolution methods apply. You just don't have to build it or maintain it.
| kkumar_70 wrote: |
I mean if clustering was desinged to be a P2P under the hoods, then architecting solutions that spans organizations is a daunty task that requires features of clustering to be used.
|
Defining any organisation-wide architecture is not something you do one lunchtime on the back of a beer mat.
| kkumar_70 wrote: |
So, it would bring us back to the statement that clustering may be advocated for smaller shops that has all their queue managers within a single network where setups could be created to make maximum out of MQ clustering.
|
No, clustering works best in large shops where a P2P (or hub & spoke) would be unweildy. Yes, if you have firewalls and other network impediments you can't just plonk a cluster down and walk away, but a few straighforward concepts, some routing decisions and off you go.
And I'd hate the FR become either a message concentrator (because everything routed through it) or a single point of failure that needs to be under massive HA. And which FR does the routing? Clusters have no less than 2.
On another point - have you ever seen application people trying to design & build workload balancing? It's not pretty.
Like I said, my 2 cents. Your site is your site, you must do what you feel is best. If that involves hundreds of P2P connections then so be it. If it's building a hub & spoke and buying HA for the hub it's your money.
Go in peace.
_________________
Honesty is the best policy.
Insanity is the best defence. |
|
| Back to top |
|
|
| kkumar_70 |
| Posted: Tue Feb 05, 2008 9:46 am Post subject: |
|
|
Novice
Joined: 04 Feb 2008
Posts: 10
|
All,
Thank you for your valuable inputs.
Here's the thing. If one does the same thing over and over again, explaining that to someone else gets dicy. Reason. We take lot of assumptions into consideration which isn't the case for the other party to whom you are explaining, because what is so naive and common/trivial for us is infact a significant amount of information.
It is not that i do not know how things work, just contradicting things at times gets the best out of oneself. And this whole thread was just to get more information out of all of us to understand the reasonings behind what works like a charm already.
I do realize that going through FR for a huge cluster would definitely create a bottlenek and the apt solution would be if clustering does a P2P, which is what it does under the covers. But i wanted to understand why does it do so as a design. Nothing more nothing less.
Thanks again for all your inputs.
Jeff. Yes, manuals and MQ go hand in hand for me. There is NO confusion in what i understand and how i believe things ought to be. Just that i wanted to get pointers from other MQ Experts as to why they think that the MQ Clustering design does a P2P and its pros/cons etc....
Thanks again to all.
Guess we may close this thread now. 
KK |
|
| Back to top |
|
|
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
|
|
