Will the Jira data center version run on only one node?

Question

We have a 500 user Jira Server edition license and we are at capacity. We were planning to upgrade to the 2000 user server edition before our renewal expires, but it appears to be the same amount to upgrade to the data center version for 1000 users (we don't have a need to add over 1000 users at the moment).  So we want to simply purchase the 1000 user data center upgrade but apply the license to our server version instance until we are ready to add additional nodes. Can we simply apply the new data center license to our server edition in the short term, and it will operate as it does now, or does this require a completely new install of the data center version? We do plan to add another node, but this will not happen anytime soon.

crf · Answer

There is good discussion elsewhere about whether or not this is really the most cost effective option for you, but to answer the technical question directly:

* It is possible to migrate from JIRA Server to JIRA Data Center (JDC) more or less in place.  Obviously, you should back up the entire system, including the file structure, before you get started.
* It is possible to run a JDC with only a single node.  The actual installation is more complicated than JIRA Server's and there are some run-time consequences to the change, as JDC does not know whether or not you intend to bring up a second node, so it must always perform the cluster-related bookkeeping that would be appropriate.  This may have performance impact, depending on exactly how the system is used.
* Not all plugins are supported in JDC, so you may need to remove some of them.  They are less likely to cause an actual problem if you are only running in a single node, but unsupported is unsupported.
* Running in a single node obviously sacrifices many of the benefits that JDC is supposed to offer, such as distribution of load, reduced downtime, and improved options recovery options (for example, if the Lucene index is corrupted on one node, it may be copied from the other).

In short, it is technically possible, but it is neither trivial nor free, so you should weigh these options (probably with, as Walter suggests, guidance from a Technical Account Manager or Expert Partner) rather than make an impulsive decision.  It may be the right long-term move and still have unacceptable short-term impact, and there may be other options they can suggest to reduce this risk.

Walter Buggenhout · Answer

https://www.atlassian.com/company/contact/purchasing-licensing

Walter Buggenhout · Answer

Hi Sean,

Data Center (and the licensing) is indeed a very different setup. Both in terms of licensing as technically. From a financial perspective, it might indeed not be the best idea to upgrade now and switch to datacenter in a few months. But mixing a data center license with your server setup is not possible.

If you plan to move to data center anyway, it might be the time to do so now. Or to repeat my advice, talk to Atlassian directly or a local Atlassian Expert to help you assess the situation and find the best solution for your situation.