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Entry  18 Apr 2017, Andreas Suter, Bug Report, run start/stop oddity  
    Reply  02 May 2017, Konstantin Olchanski, Bug Report, run start/stop oddity  
Message ID: 1288     Entry time: 02 May 2017     In reply to: 1273
Author: Konstantin Olchanski 
Topic: Bug Report 
Subject: run start/stop oddity  
I should really get around to fix this junk error message:

> 07:13:32.335 2017/04/19 [Logger,ERROR] [midas.c:14079:rpc_server_receive,ERROR]
> rpc check ok, abort canceled

What happens is this. For each run transition, cm_transition does RPC calls
to each client telling them to transition. So even if you run only on localhost, there is still
tcp connections being created and broken to do these RPCs. These connections are
typically created and left open, but when you stop odbedit, it's connections would
be closed/broken. Now in the midas rpc code there is confusion between the main rpc
connection for remote clients and temporary rpc connections for run transitions. This
confusion is the cause of these junk error messages - first the code thinks that the main rpc
connection is closed it it should commit suicide (abort), then it find that it was
just an rpc connection and there is no need to die.

> - Enable non-localhost RPC -> y
> - Disable RPC hosts check  -> y

this is unsafe:

if you only run on localhost, "enable non-localhost rpc" should be "n" and midas will no listen to any 
outside connections (except for mhttpd, of course).

if you have remote clients, enable non-localhost rpc and enter their hostnames to the access control list.

"disable rpc hosts check" is for the case where you do not know the hostnames of your remote clients, 
for example when they come from dynamic ip addresses on a wifi network.

In this case you tell midas to accept connections from everybody everywhere in the world
and hopefully you have a firewall somewhere to prevent the evil hackers from actually connecting.
I hope this is not your situation.

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