Thanks Barry. These are really helpful tips. I will probably try rest option you have suggested.
By calling this will it clear PDX registry metadata also. ((InternalClientCache) this.cache).getClientMetadataService().close(); The reason I am asking this is because we got this unknown PDX type error on client side and no matter what we do it just won't go away even after restarting client application many times. And we have PDX data persistence enabled. Even restart of Geode cluster did not work. https://stackoverflow.com/questions/51150105/apache-geode-debug-unknown-pdx-type-2140705 And this actually happened without even pool switching and in normal case. Would it possible that since we create two pools initially so one of the pool is still holding old PDX registry metadata. I understand it remains in memory and restart should solve this issue but it didn't work. We were able to solve it somehow by deploying old version of client application then hit geode and then again redeployed using new version of client application. This worked. But it is very weird. With best regards, Ashish On Tue, May 12, 2020, 4:32 AM Barry Oglesby <[email protected]> wrote: > Ashish, > > Sorry I haven't responded to this sooner, but I wanted to write a small > example to prove it works. > > I have this scenario: > > - 1 client with 1 region > - 2 servers in each of 2 distributed systems > - the client has 2 pools - 1 pointing to each set of servers > - the client also has a thread that switches the region between the pools > every N seconds using your idea of closing the region and recreating it on > the other pool > - the client is constantly doing puts > > I had some issues with single hop (pr-single-hop-enabled). If I disabled > single hop, the test worked fine. The client did puts into 1 set of > servers, then the other. > > If I enabled single-hop, the client stuck to only 1 set of servers. I > found I had to to clear the ClientMetadataService after closing the region > like: > > ((InternalClientCache) this.cache).getClientMetadataService().close(); > > I had this trouble because all the servers were up the whole time. > > Here are a few other comments: > > - Automating this is tricky. If there are any network issues between 1 > client and the servers, but not other clients, then that client may switch > over when you don't want it to. > - Assuming there is a wan connection between the sites, you'll have to > handle events in the queue that don't get sent before the clients switch. > Depending on the ops they are doing, there might be stale data. > - Automated failback is also tricky. Its better to control it. > - If the client threads are active when the switch occurs, they'll have to > handle the RegionDestroyedExceptions that occur when the region is closed > out from under them > - I don't know if your clients are REST-enabled, but a REST API to switch > pools would be pretty cool. > > Thanks, > Barry Oglesby > > > > On Wed, May 6, 2020 at 9:40 AM aashish choudhary < > [email protected]> wrote: > >> Thanks Barry you were right I was not properly resetting the pool. It >> worked after resetting it properly. Some more questions. >> >> We have same certs on prod and prod parallel cluster so we don't have to >> switch certs in the future. We don't have auth/authz enabled aa of now. May >> be we need to change few things in that case. Do you see any challanges >> with this use case?. >> >> With best regards, >> Ashish >> >> On Wed, May 6, 2020, 1:14 AM Barry Oglesby <[email protected]> wrote: >> >>> Ashish, >>> >>> The keySetOnServer call is just an example of doing something on the >>> server. >>> >>> In your example, the switchToSecondary and switchToPrimary methods are >>> recreating the regions but not resetting the pointers to region1 and >>> region2. They are still pointing to the previous (closed) instances of the >>> Region. >>> >>> Something like this should work: >>> >>> >>> this.region1 = >>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>> .setPoolName("B") >>> .create("region1"); >>> >>> Thanks, >>> Barry Oglesby >>> >>> >>> >>> On Tue, May 5, 2020 at 11:14 AM aashish choudhary < >>> [email protected]> wrote: >>> >>>> ClientCache clientCache = new ClientCacheFactory().create(); >>>> PoolFactory poolFactory = PoolManager.createFactory(); >>>> poolFactory.addLocator("Locator11", 10334); >>>> poolFactory.addLocator("Locator22", 10334); >>>> poolFactory.create("A"); >>>> >>>> poolFactory = PoolManager.createFactory(); >>>> poolFactory.addLocator("Locator33", 10334); >>>> poolFactory.addLocator("Locator44", 10334); >>>> poolFactory.create("B"); >>>> >>>> Region region11 = >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("A") >>>> .create("region1"); >>>> Region region22 = >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("A") >>>> .create("region2"); >>>> >>>> >>>> Region region33 = >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("B") >>>> .create("region1"); >>>> Region region44 = >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("B") >>>> .create("region2"); >>>> In normal scenario i don't switch pool and get Data from pool A only.To >>>> forcefully switch pools at runtime i have created and registered MBean. >>>> This MBean will have a flag for forcefully switching pools at runtime. >>>> For example if Mbean attribute secondaryPool is set to true then before >>>> fetching data it should call switchToSecondary. Likewise for the case of >>>> switching to primary pool. >>>> Sample code >>>> if(isPrimarypool){ >>>> switchToPrimary(); >>>> } >>>> if(isSecondarypool){ >>>> switchToSecondary(); >>>> } >>>> >>>> In the method switchToPrimary() this is what i am trying is something >>>> like below. >>>> switchToPrimary(){ >>>> closeRegion(); >>>> //then re-creating regions again something like this >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("A") >>>> .create("region1"); >>>> >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("A") >>>> .create("region2"); >>>> } >>>> In the method switchToSecondary() this is what i am trying is something >>>> like below >>>> switchToSecondary(){ >>>> closeRegion(); >>>> //then creating regions again >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("B") >>>> .create("region1"); >>>> >>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>> .setPoolName("B") >>>> .create("region2"); >>>> } >>>> closeRegion(){ >>>> region1.close(); >>>> region2.close(); >>>> } >>>> Now the problem is if i switch to secondaryPool from >>>> primaryPool(changing Mbean attribute value) it works. But when i try to >>>> switch back to primary it says region destroyed. >>>> Let me know if you have any doubts about my approach. Basically i am >>>> trying to follow what is explained in the link i have shared earlier. As >>>> per that i have close and re create region if i need to switch. But i can't >>>> get handle to pool regions so that i can close regions pool wise It would >>>> have been easier that way but as you said that it's not possible for region >>>> to below to two pools. >>>> >>>> Also i have looked at your code not sure why you have to call >>>> keySetOnServer() method. >>>> >>>> >>>> >>>> With Best Regards, >>>> Ashish >>>> >>>> >>>> On Tue, May 5, 2020 at 11:03 PM Barry Oglesby <[email protected]> >>>> wrote: >>>> >>>>> Yes, you can't have a single region pointing at 2 pools. What I posted >>>>> is the way I've done it in the past. I just tried it, and it still works. >>>>> Maybe if you post your full code, I can take a look. >>>>> >>>>> Thanks, >>>>> Barry Oglesby >>>>> >>>>> >>>>> >>>>> On Tue, May 5, 2020 at 10:19 AM aashish choudhary < >>>>> [email protected]> wrote: >>>>> >>>>>> Hi Barry, >>>>>> >>>>>> Thanks for the response. >>>>>> >>>>>> I am actually calling region.close() which I believe calls >>>>>> localDestroyRegion >>>>>> only. The problem is region names are same in both cluster so do how do I >>>>>> close region of cluster before switching to another cluster. I just want >>>>>> to >>>>>> switch pools based upon my use case at run-time. >>>>>> >>>>>> With best regards, >>>>>> Ashish >>>>>> >>>>>> On Tue, May 5, 2020, 10:25 PM Barry Oglesby <[email protected]> >>>>>> wrote: >>>>>> >>>>>>> Ashish, >>>>>>> >>>>>>> You're probably using region.destroyRegion to destroy the client >>>>>>> region. If so, that also destroys the region on the server. >>>>>>> >>>>>>> You should be able to use localDestroyRegion to just destroy the >>>>>>> client region like: >>>>>>> >>>>>>> // Get the region's key set using pool 1 >>>>>>> Region pool11Region = createRegion(this.pool1.getName()); >>>>>>> Set pool1Keys = pool1Region.keySetOnServer(); >>>>>>> pool1Region.localDestroyRegion(); >>>>>>> >>>>>>> // Get the region's key set using pool 2 >>>>>>> Region pool2Region = createRegion(this.pool2.getName()); >>>>>>> Set pool2Keys = pool2Region.keySetOnServer(); >>>>>>> pool2Region.localDestroyRegion(); >>>>>>> >>>>>>> The createRegion method is: >>>>>>> >>>>>>> private Region createRegion(String poolName) { >>>>>>> return this.cache >>>>>>> .createClientRegionFactory(ClientRegionShortcut.PROXY) >>>>>>> .setPoolName(poolName) >>>>>>> .create(this.regionName); >>>>>>> } >>>>>>> >>>>>>> Thanks, >>>>>>> Barry Oglesby >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Tue, May 5, 2020 at 9:37 AM aashish choudhary < >>>>>>> [email protected]> wrote: >>>>>>> >>>>>>>> Hi, >>>>>>>> >>>>>>>> I am sort of trying to implement a failover/failback for geode >>>>>>>> client. I have followed the approach the mentioned in here >>>>>>>> <https://community.pivotal.io/s/article/Configure-client-to-use-several-clusters>. >>>>>>>> I understand it's for gemfire but sharing just for reference as the use >>>>>>>> case is same and will apply this for geode as well. I hope that's ok. >>>>>>>> >>>>>>>> This is what i am trying to do. Creating two pools but in my case i >>>>>>>> have same region names in both cluster A and B. >>>>>>>> ClientCache clientCache = new ClientCacheFactory().create(); >>>>>>>> >>>>>>>> PoolFactory poolFactory = PoolManager.createFactory(); >>>>>>>> poolFactory.addLocator("Locator1", 10334); >>>>>>>> poolFactory.addLocator("Locator2", 10334); >>>>>>>> poolFactory.create("A"); >>>>>>>> >>>>>>>> poolFactory = PoolManager.createFactory(); >>>>>>>> poolFactory.addLocator("Locator1", 10334); >>>>>>>> poolFactory.addLocator("Locator2", 10334); >>>>>>>> poolFactory.create("B"); >>>>>>>> >>>>>>>> Region region11 = >>>>>>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>>>>>> .setPoolName("A") >>>>>>>> .create("region1"); >>>>>>>> >>>>>>>> Region region22 = >>>>>>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>>>>>> .setPoolName("A") >>>>>>>> .create("region2"); >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Region region33 = >>>>>>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>>>>>> .setPoolName("B") >>>>>>>> >>>>>>>> .create("region1"); >>>>>>>> >>>>>>>> Region region44 = >>>>>>>> clientCache.createClientRegionFactory(ClientRegionShortcut.PROXY) >>>>>>>> .setPoolName("B") >>>>>>>> >>>>>>>> .create("region2"); >>>>>>>> >>>>>>>> So If a client needs to connect to regions with the same name in two >>>>>>>> different distributed systems then it must close or destroy the region >>>>>>>> and recreate it with the changed pool configuration each time it wants >>>>>>>> to change between two distributed systems. >>>>>>>> >>>>>>>> I am doing the same but getting region destroyed exception instead. I >>>>>>>> am using geode java client not spring data geode. >>>>>>>> >>>>>>>> How to do this? Please help. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> With Best Regards, >>>>>>>> Ashish >>>>>>>> >>>>>>>
