Perhaps there is no way to do what you want. you have 3 servers and you want to update the configuration in all of them so that the ids are changed. Whatever you do, you will need to restart each of the servers in order for them to see the new configuration. Say you start by updating one server, if you change the sid it will not be able to connect to the other two according to your observation, so there will be an ensemble of two running. Now you either go back to the initial state or restart a server of the running ensemble. Besides, what is the practical point in this? Server id is only an arbitrary number to identify servers.
On Wed, Feb 19, 2014 at 1:51 PM, Marcin Cabaj <[email protected]>wrote: > Hi, > > Thank you for your answer. > > Zookeeper version I'm doing tests on : 3.4.5-1392090, built on 09/30/2012 > 17:52 GMT > Reconfig feature will be available in version: 3.5.0. > > Yes, you are right with rolling restart, but while I restart second > service, whole cluster will be down. > I'm trying to avoid downtime. > > -- > cheers > mc > > > > On Wed, Feb 19, 2014 at 12:31 PM, German Blanco < > [email protected]> wrote: > > > So servers do check the sid in the server list. Sorry about that. Maybe > you > > are running trunk and I work mainly with 3.4.5, or maybe I was completely > > wrong. > > Why don't you just update all files first, and then do a rolling restart? > > The first server that is restarted will not be able to join the quorum, > but > > hopefully when you restart the second it will form a quorum with the > first > > and then when you restart the third everything is back to normal. > > Or try the reconfig feature? I haven't tried it myself, but it should be > > more or less the same as updating the files. > > > > > > On Wed, Feb 19, 2014 at 1:08 PM, Marcin Cabaj <[email protected] > > >wrote: > > > > > Ok, I fixed it, > > > > > > the only thing I changed was zoo.conf > > > server.1=zoo0:2888:3888 > > > server.0=zoo1:2888:3888 > > > and restarted zoo0. > > > > > > In the meantime I've created test ensemble, to test 'changing' server > ID, > > > my start configuration: > > > > > > zoo1.conf, zoo2.conf: zoo3.conf: > > > server.41=localhost:2888:3888 > > > server.42=localhost:2889:3889 > > > server.43=localhost:2890:3890 > > > > > > zoo1/myid = 41 > > > zoo2/myid = 42 > > > zoo3/myid = 43 > > > > > > zoo3 is the LEADER > > > > > > At this moment, I can't change server id of followers:( > > > What I do: > > > 1) change zoo1/myid = 1 > > > 2) change zoo1.conf: > > > server.1=localhost:2888:3888 > > > server.42=localhost:2889:3889 > > > server.43=localhost:2890:3890 > > > 3) restart zoo1 > > > > > > in logs I see that LEADER complains about invalid server id: 1 > > > 2014-02-19 12:05:50,534 [myid:43] - WARN [localhost/127.0.0.1:3890 > > > :QuorumCnxManager@344] - Invalid server id: 1 > > > > > > Question: How to change server ID one of the servers without shutting > > down > > > whole ensemble? > > > > > > -- > > > cheers > > > mc > > > > > > > > > > > > On Tue, Feb 18, 2014 at 3:54 PM, German Blanco < > > > [email protected]> wrote: > > > > > > > Leave it as it is. Servers do no check if the sid from another server > > is > > > in > > > > that list ... At least I believe they don't, and my experience so far > > > > confirms it. And if they did it strictly, you wouldn't have reached > > your > > > > current state. > > > > > > > > On Tuesday, February 18, 2014, Marcin Cabaj < > [email protected] > > > > > > > wrote: > > > > > > > > > Thanks, will try it tomorrow. > > > > > One thing I'm wondering, if I set zoo0 id to eg 5, should I update > > > > zoo.cfg > > > > > on other servers? > > > > > If so restart is needed as well right? It will crash my cluster. Or > > > just > > > > > leave zoo.cfg as is? > > > > > > > > > > -- > > > > > cheers > > > > > mc > > > > > > > > > > > > > > > On Tue, Feb 18, 2014 at 1:41 PM, German Blanco < > > > > > [email protected] <javascript:;>> wrote: > > > > > > > > > > > For this step: > > > > > > "Set a different id in the myid file of server 0 (the one that is > > > > down), > > > > > > restart it, verify that it joins the quorum." any value that is > not > > > > used > > > > > > should do, e.g. 3, 4, 5, 1231 ... > > > > > > > > > > > > > > > > > > On Tue, Feb 18, 2014 at 12:04 PM, German Blanco < > > > > > > [email protected] <javascript:;>> wrote: > > > > > > > > > > > > > Hello! > > > > > > > Set a different id in the myid file of server 0 (the one that > is > > > > down), > > > > > > > restart it, verify that it joins the quorum. > > > > > > > If it joins the quorum, set the myid value in server 1 to one, > > > > restart > > > > > > it, > > > > > > > verify that it joins the quorum. > > > > > > > If it joins the quorum, update again the myid file of server 0, > > > this > > > > > time > > > > > > > to the correct 0 value. Restart, verify that it all works. > > > > > > > > > > > > > > If any of the steps fails, stop and think it all over again. > > > > > > > > > > > > > > Good luck. > > > > > > > > > > > > > > > > > > > > > On Tuesday, February 18, 2014, Marcin Cabaj < > > > > [email protected]<javascript:;> > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > >> Hi all, > > > > > > >> > > > > > > >> My ZooKeeper ensemble contains 3 servers, unfortunately > somehow > > > > > servers > > > > > > >> ids > > > > > > >> have been messed up. > > > > > > >> > > > > > > >> zoo.cfg on all servers: > > > > > > >> server.0=zoo0:2888:3888 > > > > > > >> server.1=zoo1:2888:3888 > > > > > > >> server.2=zoo2:2888:3888 > > > > > > >> > > > > > > >> but: > > > > > > >> on ZOO0: > > > > > > >> [xxx@zoo0]$ cat /var/zookeeper/myid > > > > > > >> 1 > > > > > > >> [xxx@zoo0]$ echo conf | nc localhost 2181 > > > > > > >> This ZooKeeper instance is not currently serving requests > > > > > > >> > > > > > > >> on ZOO1: > > > > > > >> [xxx@zoo1] $ cat /var/zookeeper/myid > > > > > > >> 0 > > > > > > >> [xxx@zoo1:~]$ echo conf | nc localhost 2181 | grep serverId > > > > > > >> > > > > > > >> serverId=0 > > > > > > >> > > > > > > >> on ZOO2: > > > > > > >> [xxx@zoo2:~]$ cat /var/zookeeper/myid > > > > > > >> 2 > > > > > > >> [xxx@zoo2:~]$ echo conf | nc localhost 2181 | grep serverId > > > > > > >> serverId=2 > > > > > > >> > > > > > > >> How to fix this without shutting down whole ensemble? > > > > > > >> Currently I have connections established to ZOO1 and ZOO2. > > > > > > >> ZOO0 is listening on 2181 but doesn't accept connections. > > > > > > >> ZOO2 is the leader. > > > > > > >> > > > > > > >> Zookeeper version: 3.3.5-cdh3u5--1, built on 10/06/2012 01:58 > > GMT > > > > > > >> > > > > > > >> Cheers > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > >
