Random Musings of a toddler: 2011

Machine 1:

1. Install ejabberd as a cluster node on machine 1 (Node name: ejabberd@PrasadK)

2. Configure it to use mysql database based on the installation guide.

3. Started the server using windows services. (You can alternatively start it from command line using $ejabberd-installation/bin/ejabberdctl start)

Machine 2:

1. Install ejabberd as a cluster node on machine 2 (Nodename: ejabberd@riktam-acb56375)

2. Configure it to use mysql database (the same server which the first machine's ejabberd server is connected to)

3. Copy the .erlang.cookie file (which resides in C:/Windows folder if it's started as a service or $USER_HOME folder if it's started via command line) from the machine 1 to the machine 2's home folder. (I copied it in two places - in bin folder where erl command is executed and the user's home folder. Need to confirm which of them is used)

4. Execute the command from $ejabberd-installation/bin/ directory

D:\ejabberd\bin>erl -sname ejabberd@riktam-acb56375 -mnesia extra_db_nodes "['ejabberd@PrasadK']" -s mnesia

5. Executing the above command should enter into erlang shell which looks like:

Eshell V5.6.4 (abort with ^G)

(ejabberd@riktam-acb56375)1>

a) execute mnesia:info(). to check if the two nodes are shown in running_nodes. If not check your ejabberd.log file:

(ejabberd@riktam-acb56375)1>mnesia:info().

---> Processes holding locks <---

---> Processes waiting for locks <---

---> Participant transactions <---

---> Coordinator transactions <---

---> Uncertain transactions <---

---> Active tables <---

schema : with 29 records occupying 3580 words of mem

===> System info in version "4.4.5", debug level = none <===

opt_disc. Directory "d:/ejabberd/bin/Mnesia.ejabberd@riktam-acb56375" is NOT use

d.

use fallback at restart = false

running db nodes = [ejabberd@PrasadK,'ejabberd@riktam-acb56375']

stopped db nodes = []

master node tables = []

remote = [acl,caps_features,captcha,config,http_bind,iq_response,

irc_custom,local_config,mod_register_ip,motd,motd_users,

muc_online_room,muc_registered,muc_room,passwd,

pubsub_index,pubsub_item,pubsub_last_item,pubsub_state,

pubsub_subscription,reg_users_counter,route,s2s,session,

session_counter,sql_pool,sr_group,sr_user]

ram_copies = [schema]

disc_copies = []

disc_only_copies = []

[] = [sql_pool,local_config,caps_features,mod_register_ip]

[{ejabberd@PrasadK,disc_copies}] = [config,pubsub_subscription,passwd,

irc_custom,sr_user,motd,acl,pubsub_index,

sr_group,motd_users,muc_room,pubsub_state,

muc_registered]

[{ejabberd@PrasadK,disc_copies},{'ejabberd@riktam-acb56375',ram_copies}] = [sche

ma]

[{ejabberd@PrasadK,disc_only_copies}] = [pubsub_item]

[{ejabberd@PrasadK,ram_copies}] = [http_bind,reg_users_counter,

pubsub_last_item,route,s2s,captcha,

session_counter,session,iq_response,

muc_online_room]

3 transactions committed, 0 aborted, 0 restarted, 0 logged to disc

0 held locks, 0 in queue; 0 local transactions, 0 remote

0 transactions waits for other nodes: []

ok

b) Now run the following in the same `erl' session:

(ejabberd@riktam-acb56375)2> mnesia:change_table_copy_type(schema, node(), disc_copies).

c) Now you can add replicas of various tables to this node with `mnesia:add_table_copy'

or `mnesia:change_table_copy_type' as above (just replace `schema' with another table

name and `disc_copies' can be replaced with `ram_copies' or `disc_only_copies').

d) Run `init:stop().' or just `q().' to exit from the Erlang shell. This probably can take

some time if Mnesia has not yet transfered and processed all data it needed from first.