Re: Some questions about Zookeeper 3.2.0
A related question. If I have run a Zookeeper service with many ephemeral znodes on five servers, then I want to replace one of the servers by a new one, and the new server has a new IP. How can I do the job without any loss of data ? Thanks On Mon, Jun 29, 2009 at 9:24 AM, Qian Ye yeqian@gmail.com wrote: Thanks for the explanation, it sounds great. It seems that I should study more on Zookeeper :-) regards On Mon, Jun 29, 2009 at 2:15 AM, Ted Dunning ted.dunn...@gmail.comwrote: I don't think you should be very nervous at all. There are two questions: 1) can 3.1.1 go to 3.2 with no down time. This is very likely, but a wiser head than mine should have final say 2) can 3.1.1 go to 3.2 with 1 minute of downtime. The is for sure. Neither option involves data loss. ZK is actually really really good for HA operations. On Sun, Jun 28, 2009 at 4:55 AM, Qian Ye yeqian@gmail.com wrote: your answer makes me nervous about upgrade Zookeeper server -- With Regards! Ye, Qian Made in Zhejiang University -- With Regards! Ye, Qian Made in Zhejiang University
Re: Some questions about Zookeeper 3.2.0
A rolling update works very well for that. You can also change the number of nodes in the cluster. To do this, you replace the config files on the surviving servers and on the new server. Then take down the one that is leaving the cluster and then one by one restart the servers that will remain in the cluster. Then start the new server. If you only have 3 ZK servers, you might want to do the upgrade in two steps if you are totally paranoid about running with just 2 servers in your cluster. In that scenario, you would add the new server to the config and restart each of the 3 ZK servers and staring the new one. That gives you a ZK cluster with 4 servers. Another rolling update can reconfigure it to have only the 3 servers you want. Make sure you leave several seconds between restarting each server. That will give the cluster time to calm down and do any necessary leader elections On Sun, Jun 28, 2009 at 11:03 PM, Qian Ye yeqian@gmail.com wrote: A related question. If I have run a Zookeeper service with many ephemeral znodes on five servers, then I want to replace one of the servers by a new one, and the new server has a new IP. How can I do the job without any loss of data ?
Re: ZK quota
Do we have a JIRA for this? If not we should add one for 3.3. Patrick Mahadev Konar wrote: Hi Raghu, We do have plans to enforce quota in future. Enforcing requires some more work then just reporting. Reporting is a good enough tool for operations to manage a zookeeper cluster but we would certainly like to enforce it in the near future. Thanks mahadev On 6/18/09 7:01 PM, rag...@yahoo.com rag...@yahoo.com wrote: Is there a reason why node count/byte quota is not actually enforced but rather ZK just warns? Are there any plans to enforce the quota in a future release? Thanks Raghu
