Thanks Karl, I have a little variation here and this is about having both MCF nodes in Active/Active nodes pointing to same DB, so still Zookeeper is required?
Also does it mean by " two sets of three zookeeper machines", i need to setup three zookeepers onto each node so total 6 zookepeer node here working on both machine in same ensamble? Regards. On Mon, Jun 30, 2014 at 6:50 PM, Karl Wright <[email protected]> wrote: > Hi Lalit, > > You can keep things really simple by having both active and passive mcf > instances run each as a single process, either under jetty or using the > combined war under tomcat. If that is not acceptable, you would need two > sets of three zookeeper machines, one set for each instance. > > Karl > > Sent from my Windows Phone > ------------------------------ > From: lalit jangra > Sent: 6/30/2014 12:19 PM > To: [email protected] > Subject: Re: Zookeeper in Apache ManifoldCF > > Thanks Karl & Graeme, > > Let me elaborate my scenario and what i am trying to achieve. > > I have two servers each running MCF 1.5.1 individually. But both of them > are backed by same PostGreSQL DB so both of MCF applications are pointing > to same DB at any point of time, without having their own dedicated DBs. > Next, primary/active DB instance is backed up with periodical backups from > active to passive instance. > > Only one DB instance will be active at any time, with other DB instance > acting as active standby. In case of breakdown of primary/active instance, > passive/secondary will take over and becomes primary/active instance > handling all DB transactions, thus making primary as new secondary DB > instance. > > Similarly i have two solr 4.6 instances which act in active/passive mode > with periodic backup of active/primary to passive/secondary with active > standby and failover. > > So my intention of clustering is high availability of system with failover > but i will not use both of MCF instances parallely or simultaneously. > > Finally i am limited to having two instances only but as mentioned > earlier, we need at least three Zookeeper instances for a proper Zookeeper > clustering. > > Is it still worthy to go and use Zookeeper or i can do simple clustering > where each of MCF node is clustered using same DB. Please suggest. > > Thanks for help. > > Regards. > > > On Fri, Jun 27, 2014 at 11:15 AM, Graeme Seaton <[email protected]> wrote: > >> Hi Lalit, >> >> For production use, you will want to spin up your own ZK cluster using >> the instructions on the zookeeper site (as pointed out earlier at least 3 >> is recommended).... >> >> You then need to modify the properties.xml file in >> multiprocess-zk-example to point to the list of Zookeeper servers. You >> also need to modify properties-global.xml with the appropriate global >> settings i.e. logging levels, Postgresql database etc. and then run >> setglobalproperties.sh to register the settings in ZK. >> >> To test that is working, set up a crawl and then tail the manifoldcf.log >> file on each of your nodes to check that they are all crawling in parallel. >> >> HTH, >> >> Graeme >> >> >> On 25/06/14 12:19, Karl Wright wrote: >> >> Hi Lalit, >> >> Zookeeper does not use a database; it keeps its stuff in the local file >> system. Each Zookeeper node has its own local data, and everything else is >> socket communication between them. >> >> As for information: http://zookeeper.apache.org/ >> >> Karl >> >> >> >> On Wed, Jun 25, 2014 at 6:56 AM, lalit jangra <[email protected]> >> wrote: >> >>> Thanks Karl, >>> >>> Apologies as i am not very familiar with Zookeeper and trying to figure >>> out on same. >>> >>> Is there any more documentation/pointers available for same as that >>> would be more helpful. >>> >>> Also i have 2 tomcat servers in cluster, each having MCF 1.5.1 setup >>> and configured to point to same PostGreSQL DB & DB is backed up for >>> failover. From your inputs, it seems that we need to configure a separate >>> standalone Zookeeper server which will act as Master and both nodes in >>> cluster will need to work as slaves and talk to standalone Zookeeper master. >>> >>> Also the Zookeeper server will have its own DB so either we can host >>> it separately or we can use same Postgres DB? >>> >>> Regards. >>> >>> >>> >>> On Wed, Jun 25, 2014 at 11:33 AM, Karl Wright <[email protected]> >>> wrote: >>> >>>> Hi Lalit, >>>> >>>> 1. zookeeper is already spun into MCF. in fact you start a zookeeper >>>> instance when you run the mcf zookeeper example. They recommend, though, >>>> that for failover you have 3 instances, etc. >>>> 2. Looks like the documentation is out of date and something old is >>>> left in there. >>>> 3. Zookeeper is a client/server kind of arrangement. You need at >>>> least ONE zookeeper server, and each cluster member includes a zookeeper >>>> client, which is configured to talk with ALL the zookeeper server instances >>>> you have. >>>> 4. There is ONE database instance; the instance may be supported by >>>> failover and redundant Postgresql, but it appears as one instance. TO get >>>> failover from Postgres you need the Enterprise Edition, which costs money. >>>> >>>> Karl >>>> >>>> >>>> >>>> >>>> On Wed, Jun 25, 2014 at 4:47 AM, lalit jangra <[email protected] >>>> > wrote: >>>> >>>>> Thanks Karl, >>>>> >>>>> That was helpful. >>>>> >>>>> I am setting clustered setup on Tomcats as i was following >>>>> instructions @ >>>>> http://manifoldcf.apache.org/release/trunk/en_US/how-to-build-and-deploy.html#Simplified+multi-process+model+using+ZooKeeper-based+synchronization >>>>> and i need some suggestions here. >>>>> >>>>> 1. Do we need to download zookeeper and put it in >>>>> multiprocess-zk-example folder or it is already spun into MCF and we are >>>>> good to go? >>>>> 2. It says all jars under *processes *should be put into classpath >>>>> but i can not see any *processes *folder under MCF? >>>>> 3. Do we need to setup Zookeeper on both nodes or only at one node, i >>>>> assume we need to do on both nodes ? >>>>> 4. Do we also need to setup databases separately on both nodes again. >>>>> Also can we setup Zookeeper DB using same PostGreSQL or it will use its >>>>> own >>>>> HSQL DB? >>>>> >>>>> Finally how can i test that my Zookeeper is setp and ready to roll? >>>>> >>>>> Thanks for your help. >>>>> >>>>> Regards. >>>>> >>>>> >>>>> On Tue, Jun 24, 2014 at 1:56 PM, Karl Wright <[email protected]> >>>>> wrote: >>>>> >>>>>> Hi Lalit, >>>>>> ZooKeeper is standard for cluster deployments these days. See the >>>>>> multiprocess-zookeeper example for ideas about how to deploy it. It's >>>>>> also >>>>>> important to read the how-to-build-and-deploy page to understand the >>>>>> example. >>>>>> >>>>>> Thanks, >>>>>> Karl >>>>>> >>>>>> >>>>>> >>>>>> On Tue, Jun 24, 2014 at 8:04 AM, lalit jangra < >>>>>> [email protected]> wrote: >>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> I am planning to use MCF in cluster mode. For same, i want to know >>>>>>> if Zookeeper is of any help here? >>>>>>> >>>>>>> If yes, how can it be leveraged in distributed MCF servers? >>>>>>> >>>>>>> Regards, >>>>>>> Lalit Jangra. >>>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> Regards, >>>>> Lalit Jangra. >>>>> >>>> >>>> >>> >>> >>> -- >>> Regards, >>> Lalit Jangra. >>> >> >> >> > > > -- > Regards, > Lalit Jangra. > -- Regards, Lalit Jangra.
