[rabbitmq-discuss] Clustering - just can't get it going

• Previous message: [rabbitmq-discuss] Clustering - just can't get it going
• Next message: [rabbitmq-discuss] Clustering - just can't get it going
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

This is rabbitmq 3.1.5 - I'm not sure what the erlang version is, but the
erts version is 5.8.5.  I'm a little new to the whole erlang thing, so I
just picked a component with 'e' in it :P

I'm planning to get these machines into the DNS proper to see if that
helps.  It would be pretty weird if it works, since everyone else works OK
with just /etc/hosts resolution, but it's worth a try.


On 25 September 2013 11:16, Simon MacMullen <simon at rabbitmq.com> wrote:

> You may (depending on Erlang version) need to make sure that each machine
> can resolve its own hostname too, as well as the other one.
>
> Cheers, Simon
>
> On 25/09/13 16:04, Derek Wyatt wrote:
>
>> Damn. That's exactly the setup I have.
>>
>>
>> On 25 September 2013 10:55, Robin Lawrie - HostelBookers
>> <Robin.Lawrie at hostelbookers.**com <Robin.Lawrie at hostelbookers.com><mailto:
>> Robin.Lawrie@**hostelbookers.com <Robin.Lawrie at hostelbookers.com>>>
>> wrote:
>>
>>     Hi,
>>
>>     In my case, I have a 2 node cluster (called cache1 and cache2) and I
>>     needed to add an entry to the hosts file on both nodes to ensure
>>     each node can resolve the name of the other node before clustering
>>     worked for me.
>>
>>     My hosts file is in /etc and is called hosts
>>
>>     In there I entered the following:
>>
>>     On cache1.lon.hosting, enter the line 192.168.3.1 Cache2.domain.com
>>     <http://Cache2.domain.com> Cache2
>>
>>     On cache2.lon.hosting, enter the line 192.168.3.0 Cache1.domain.com
>>     <http://Cache1.domain.com> Cache1
>>
>>     Once done, I needed to confirm I could ping each node using it’s
>>     hostname from the other node. I don’t care about DNS or nslookup
>>     working/resolving the name.
>>
>>     HTH
>>
>>     Robin
>>
>>     *From:*rabbitmq-discuss-**bounces at lists.rabbitmq.com<rabbitmq-discuss-bounces at lists.rabbitmq.com>
>>     <mailto:rabbitmq-discuss-**bounces at lists.rabbitmq.com<rabbitmq-discuss-bounces at lists.rabbitmq.com>
>> >
>>     [mailto:rabbitmq-discuss-**bounces at lists.rabbitmq.com<rabbitmq-discuss-bounces at lists.rabbitmq.com>
>>     <mailto:rabbitmq-discuss-**bounces at lists.rabbitmq.com<rabbitmq-discuss-bounces at lists.rabbitmq.com>>]
>> *On Behalf Of
>>     *Derek Wyatt
>>     *Sent:* 25 September 2013 15:47
>>     *To:* Discussions about RabbitMQ
>>     *Subject:* Re: [rabbitmq-discuss] Clustering - just can't get it going
>>
>>     Ah, I do have more information though:
>>
>>     DIAGNOSTICS
>>
>>     ===========
>>
>>     nodes in question: ['RMQ1']
>>
>>     hosts, their running nodes and ports:
>>
>>     - unable to connect to epmd on RMQ1: nxdomain (non-existing domain)
>>
>>     current node details:
>>
>>     - node name: 'rabbitmqctl1577 at RMQ2'
>>
>>     - home dir: /var/lib/rabbitmq
>>
>>     - cookie hash: ohQKEF09peb6bAgNqawvKA==
>>
>>     And just to be clear, the cookie is the same:
>>
>>     *01*:~$ sudo md5sum /var/lib/rabbitmq/.erlang.**cookie
>>
>>     a2140a105d3da5e6fa6c080da9ac2f**28  /var/lib/rabbitmq/.erlang.**
>> cookie
>>
>>     *02*:~$ sudo md5sum /var/lib/rabbitmq/.erlang.**cookie
>>
>>     a2140a105d3da5e6fa6c080da9ac2f**28  /var/lib/rabbitmq/.erlang.**
>> cookie
>>
>>     Somehow, telnet to epmd works just fine, but something that RMQ is
>>     doing fails to make that happen.  Is there some sort of DNS work
>>     that it's doing, instead of using the hosts files?
>>
>>     i.e. one thing I found is that nslookup fails:
>>
>>     02:~$ nslookup RMQ1
>>
>>     ;; Got SERVFAIL reply from <ipaddress>, trying next server
>>
>>     Server:       <ipaddress>
>>
>>     Address:  <ipaddress>
>>
>>     ** server can't find RMQ1: SERVFAIL
>>
>>     But if I ping RMQ1 it works fine. /etc/nsswitch.conf specifies that
>>     files should be tried first, before DNS w.r.t. hosts.
>>
>>     So, it looks like RMQ is doing something more rigorous to resolve
>>     the host, and I don't know how to change that.  I also don't have
>>     access to the DNS server configuration in order to modify it in any
>> way.
>>
>>     On 25 September 2013 09:57, Jason McIntosh <mcintoshj at gmail.com
>>     <mailto:mcintoshj at gmail.com>> wrote:
>>
>>     Check your erlang cookie on both servers to make sure it matches I
>>     think it's in - /var/lib/rabbitmq/ - then you can use rabbitmqctl
>>     from one machine and see if you can connect to another to list
>>     queues.  I THINK that's rabbitmqctl -n <servernode> list_queues for
>>     example.  If both servers can talk to each other then it should be
>>     rabbitmqctl stop_app, join_cluster, start_app.
>>
>>     Jason
>>
>>     On Wed, Sep 25, 2013 at 8:50 AM, Derek Wyatt <derek at derekwyatt.org
>>     <mailto:derek at derekwyatt.org>> wrote:
>>
>>     Hi,
>>
>>     I've seen a number of people failing to get clustering running and,
>>     unfortunately, I can't get it going either.  Here's the summary of
>>     what I've got:
>>
>>       * Two nodes - RMQ1 and RMQ2
>>       * I can ping RMQ1 from RMQ2, and vice versa
>>       * I can telnet from RMQ1 to RMQ2:epmd, and vice versa
>>       * I can telnet from RMQ1 to RMQ2:amqp, and vice versa
>>       * The cookie file is identical, as is clear from the startup INFO
>>
>>     My goal is to have RMQ2 join RMQ1 in a cluster.
>>
>>     The servers are started using the init script in Ubuntu (i.e.
>>     service rabbitmq-server start).  This is different than the script
>>     at http://www.rabbitmq.com/**clustering.html<http://www.rabbitmq.com/clustering.html>,
>> which says to start with
>>     "rabbitmq-server -detached".  I've tried that and it doesn't seem to
>>     make any difference so I always use the init script instead.
>>
>>     So, the script says to stop the RMQ2 server and then join the
>>     cluster.  The following transcript shows how well all this goes:
>>
>>     02:~$ sudo rabbitmqctl stop_app
>>
>>     Stopping node 'rabbit at RMQ2' ...
>>
>>     ...done.
>>
>>     02:~$ sudo rabbitmqctl join_cluster --ram rabbit at RMQ1
>>
>>     Clustering node 'rabbit at RMQ2' with 'rabbit at RMQ1' ...
>>
>>     Error: {cannot_discover_cluster,"The nodes provided are either
>>     offline or not running"}
>>
>>     However, as I said above, telnetting to the ports works just fine:
>>
>>     02:~$ telnet RMQ1 epmd
>>
>>     Trying <ip address>...
>>
>>     Connected to RMQ1
>>
>>     Escape character is '^]'.
>>
>>     booger!
>>
>>     Connection closed by foreign host.
>>
>>     02:~$ telnet RMQ1 amqp
>>
>>     Trying <ip address>...
>>
>>     Connected to RMQ1
>>
>>     Escape character is '^]'.
>>
>>     booger!
>>
>>     AMQP Connection closed by foreign host.
>>
>>     I'm stuck for what else to test.  Does anyone know how to
>>     troubleshoot this thing further?
>>
>>     Thanks,
>>
>>     Derek
>>
>>
>>     ______________________________**_________________
>>     rabbitmq-discuss mailing list
>>     rabbitmq-discuss at lists.**rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>>     <mailto:rabbitmq-discuss@**lists.rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>> >
>>     https://lists.rabbitmq.com/**cgi-bin/mailman/listinfo/**
>> rabbitmq-discuss<https://lists.rabbitmq.com/cgi-bin/mailman/listinfo/rabbitmq-discuss>
>>
>>
>>
>>     --
>>     Jason McIntosh
>>     http://mcintosh.poetshome.com/**blog/<http://mcintosh.poetshome.com/blog/>
>>     573-424-7612 <tel:573-424-7612>
>>
>>
>>     ______________________________**_________________
>>     rabbitmq-discuss mailing list
>>     rabbitmq-discuss at lists.**rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>>     <mailto:rabbitmq-discuss@**lists.rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>> >
>>     https://lists.rabbitmq.com/**cgi-bin/mailman/listinfo/**
>> rabbitmq-discuss<https://lists.rabbitmq.com/cgi-bin/mailman/listinfo/rabbitmq-discuss>
>>
>>     ------------------------------**------------------------------**
>> ------------
>>
>>     This email is from Hostelbookers.com Limited. Registered office:
>>     52-54 High Holborn, London, WC1V 6RL, UK. Registered in England
>>     under Company No.: 2841908. This email and any files transmitted
>>     with it are confidential and may be privileged and are intended
>>     solely for the use of the individual or entity to whom they are
>>     addressed. As email can be subject to operational or technical
>>     difficulties and time delays, communications that are subject to
>>     deadlines should also be sent by post. Any unauthorised direct or
>>     indirect dissemination, distribution or copying of this message and
>>     any attachments is strictly prohibited. If you have received the
>>     email in error, please notify postmaster at hostelbookers.com
>>     <mailto:postmaster@**hostelbookers.com <postmaster at hostelbookers.com>
>> >
>>
>>     ------------------------------**------------------------------**
>> ------------
>>
>>     ______________________________**_________________
>>     rabbitmq-discuss mailing list
>>     rabbitmq-discuss at lists.**rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>>     <mailto:rabbitmq-discuss@**lists.rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>> >
>>     https://lists.rabbitmq.com/**cgi-bin/mailman/listinfo/**
>> rabbitmq-discuss<https://lists.rabbitmq.com/cgi-bin/mailman/listinfo/rabbitmq-discuss>
>>
>>
>>
>>
>> ______________________________**_________________
>> rabbitmq-discuss mailing list
>> rabbitmq-discuss at lists.**rabbitmq.com<rabbitmq-discuss at lists.rabbitmq.com>
>> https://lists.rabbitmq.com/**cgi-bin/mailman/listinfo/**rabbitmq-discuss<https://lists.rabbitmq.com/cgi-bin/mailman/listinfo/rabbitmq-discuss>
>>
>>
>
> --
> Simon MacMullen
> RabbitMQ, Pivotal
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rabbitmq.com/pipermail/rabbitmq-discuss/attachments/20130925/ba1d85fd/attachment.htm>

• Previous message: [rabbitmq-discuss] Clustering - just can't get it going
• Next message: [rabbitmq-discuss] Clustering - just can't get it going
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]