I think we should get DHIS2 added to that list of systems (typically) running on Tomcat. It is a MoinMoin wiki, so I thought I could just add us, but it seems this is an "immutable" page..
On Sun, Sep 22, 2013 at 7:19 AM, Jason Pickering < jason.p.picker...@gmail.com> wrote: > Hi Thanh, > > First off, be sure you are aware of who you are dealing with in such a > debate. These "commercial companies" are probably a lot better at you in > selling products to people who do not need them than you are. This is after > all, what they do. So, keeping that in mind, lets pick apart what they are > saying. > > "DHIS2 is not built on and use well-know reliable solutions such as > Microsoft Sharepoint, IBM Websphere, Oracle Bea Weblogic" > > No reason why you could not used DHIS2 with Websphere or Weblogic in > theory. Of course, it would be a huge waste of money to plonk down money > for these applications, when Apache Tomcat (which is free) will do the job > just fine. DHIS2 is using Spring and not EJB, so there is simply no need > for these products. As for Sharepoint, well, it is a totally different > application stack, and not really interesting to debate about. Point is > DHIS2 is built using Java and lots of standard open-source libraries used > by lots of other projects (including commercial ones). So which application > server it uses is really a mater of choice. You could take Tomcat, and it > would work fine. You could also pay a company a lot of money for > a licence for one of the products you mention. Here is a partial list of > companies/projects using Tomcat, and the number is not small ( > http://wiki.apache.org/tomcat/PoweredBy) > > >1. When multiple DHIS2 instances can be deployed in multiple servers > (virtual or physical) and load balanced by a hard or soft balancer > (nginxs), this can not solve the real >problem of distributed HTTP sessions > like what can be done in Application Server, i.e. a logged in users > connected to a instance and this instance die, how can they continue > >without relogin. > >Can using Application Server solve the problems without having to rewrite > dhis2? > > > Which Application Server? I guess my question here would be what is the > impact of a clustered Tomcat instance crashing? OK, maybe the user has to > login again. Maybe they loose a little bit of work at worst. So what? Not > that this is not an impact, but would it justify even an attempt to > implement a load-balanced clustered solution with some sort of failover > protection transparent to the user? It would not really seem to be > justified. > > >How are we going to solve this? Will we need to use commercial solutions > like Terracotta BigMemory or IBM Data Grid? > > What is the point? This again sounds like a bit of a snake-oil argument > here. These products are not going to help with the issue of an application > server failing. . > > >3. I would like to know the typical deployment of dhis2 in other > countries. Is that on one or multiple server, with or without database > clusters? I heard that many countries go for >cloud but I am not sure if it > is a single or multiple cloud servers? > > Most countries which I know of are using a rather modest server. Many are > using the cloud, some are not. Many countries have everything on the same > machine (database, application server, nginx) and separating the database > and application server is fairly typical as well. But I could imagine > there are some installations out there which are using clusters, but I > would say this is probably not typical (yet) of most DHIS2 installations. > > > >Can cloud provide us a single virtual but unlimited RAM and CPUs server? > As if yes, then we don't have to worry about question 1, 2 because we can > simple add 10000000 >GB RAM and 100000 CPUs to that cloud server. > > Well, for all intents and purposes, you could continue to increase the > size of the server up to a certain size as required but I think the metrics > you give there are pretty ridiculous.Why would you need that much RAM or > CPU power? Even if it were physically possible which seems reasonable > (although likely very very expensive) , it would generally not make much > sense to do this. Probably better to break the system up into smaller > pieces instead. Using many small servers to distribute the process is > typically the favored approach, instead of having one big massive machine. > > Anyway, there are a few thoughts off the top of my head. In summary, there > is simply no need for the commercial products you mention in the vast > majority of use cases we have come across. Not to say that they do not > exist, but I would press these "companies" for more details on how these > are actual requirements, and not simply invented hypothetical cases which > could potentially be used to make a sale of unneeded licences. > > Regards, > Jason > > > > On Sun, Sep 22, 2013 at 3:14 AM, Ngoc Thanh Nguyen < > thanh.hispviet...@gmail.com> wrote: > >> Hi all, >> >> Some commercial affiliated companies want to kick dhis2 out so they made >> the following arguments: "DHIS2 is not built on and use well-know reliable >> solutions such as Microsoft Sharepoint, IBM Websphere, Oracle Bea Weblogic" >> >> When most of this is wrong they have some valid points that we need to be >> prepared in order to fight back. I would like to get your ideas on >> >> 1. When multiple DHIS2 instances can be deployed in multiple servers >> (virtual or physical) and load balanced by a hard or soft balancer >> (nginxs), this can not solve the real problem of distributed HTTP sessions >> like what can be done in Application Server, i.e. a logged in users >> connected to a instance and this instance die, how can they continue >> without relogin. >> >> Can using Application Server solve the problems without having to rewrite >> dhis2? >> >> How are we going to solve this? Will we need to use commercial solutions >> like Terracotta BigMemory or IBM Data Grid? >> >> 2. For database scale, with one database instances installed on single >> server. it has the risk of data loss. We can use database clusters to >> address this issue, and data on clusters mostly rely on memory. My question >> is how this cluster will work with distributed sessions described in >> question 1. >> >> 3. I would like to know the typical deployment of dhis2 in other >> countries. Is that on one or multiple server, with or without database >> clusters? I heard that many countries go for cloud but I am not sure if it >> is a single or multiple cloud servers? >> >> Can cloud provide us a single virtual but unlimited RAM and CPUs server? >> As if yes, then we don't have to worry about question 1, 2 because we can >> simple add 10000000 GB RAM and 100000 CPUs to that cloud server. >> >> Thanks in advanced. >> >> Thanh >> >> >> >> >> >> _______________________________________________ >> Mailing list: https://launchpad.net/~dhis2-devs >> Post to : dhis2-devs@lists.launchpad.net >> Unsubscribe : https://launchpad.net/~dhis2-devs >> More help : https://help.launchpad.net/ListHelp >> >> > > _______________________________________________ > Mailing list: https://launchpad.net/~dhis2-devs > Post to : dhis2-devs@lists.launchpad.net > Unsubscribe : https://launchpad.net/~dhis2-devs > More help : https://help.launchpad.net/ListHelp > > -- Knut Staring Dept. of Informatics, University of Oslo +4791880522 http://dhis2.org
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