Hi,

When I tried to deploy slony-2.0.4, there have a problem I met during slave
node configuration. Maser node slon process looks hang and there is *<event
pending>* in pa_conninfo of sl_path table. Below is the output of that
table.

[root at slony-r1s1-001 ~]# psql -U postgres system.db -c "select * from
_slony.sl_path"
 pa_server | pa_client |
pa_conninfo                                       | pa_connretry
-----------+-----------+-----------------------------------------------------------------------------+--------------
2 |         1 | host=192.168.11.12 dbname=system.db user=postgres
port=5432|           10
1 |         2 | <event
pending>
|           10


Here is the configuration sequence I used to setup master and slave, I used
atlperl related tools to configure slon.
*On master node:*

   1. Configure and start postgresql service
   2. Configure slon using slonik_init_cluster and
   slony_define_replication_set
   3. Start slon service

*On slave node:*

   1. Configure and start postgresql service
   2. Configure slon using slonik_store_node and slonik_subscribe_set
   3. Start slon service

The incorrect configuration in sl_path will cause master node hangs and
master will not generate any new SYNC event. However, *after about 7 hours,
*the information in sl_path becomes correct configuration and SYNC event can
be generated.

After check slony source, I was thinking the issue might happen during
subscribeSet and add some logs in backend script slony1_funcs.sql. However,
it looks like subscribeSet and enableSubscription finished successfully from
slon log. I also checked slon thread info, there is no
remoteListenThread_main and remoteWorkerThread_main thread comparing with
normal slon process in the master node.

My question are:

   1. Is there any other things we can check in the slony table or logs?
   2. Why there need to wait for 7 hours for that correct sl_path? Does
   there has anything block master node?
   3. Do you think this is a configuration issue or issue inside slony
   source code?


Thanks,
Jason
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