Bug 202995

Summary: Unexpected connection attempts - Connect failed with rc -113: No route to host
Product: Red Hat Enterprise Linux 4 Reporter: Tom Fredian <twf>
Component: iscsi-initiator-utilsAssignee: Mike Christie <mchristi>
Status: CLOSED CURRENTRELEASE QA Contact: Brock Organ <borgan>
Severity: medium Docs Contact:
Priority: medium    
Version: 4.4CC: 157070.alewis, coughlan, mwill
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Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: 4.5 Doc Type: Bug Fix
Doc Text:
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Clone Of: Environment:
Last Closed: 2007-11-14 14:03:30 UTC Type: ---
Regression: --- Mount Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Tom Fredian 2006-08-17 18:28:09 UTC
Description of problem:

We have a single iscsi based external raid device networked to an RHEL4 system 
via a straight cable connection (no switches or hubs). The /etc/iscsi.conf 
contains a very simple configuration with a single line containing the 
DiscoveryAddress of the raid system. This configuration worked fine with RHEL3 
and (except for the following error messages which now show up on the console 
and in /var/log/messages) still works just fine.

Approximately every 10 seconds the following appears in /var/log/messages:

Aug 17 10:23:51 alcserv3 kernel: iscsi-sfnet:host5: Connect failed with rc -
113: No route to host
Aug 17 10:23:51 alcserv3 kernel: iscsi-sfnet:host5: establish_session failed. 
Could not connect to target
Aug 17 10:23:51 alcserv3 kernel: iscsi-sfnet:host5: Waiting 10 seconds before 
next login attempt

Version-Release number of selected component (if applicable):

Linux alcserv3.psfc.mit.edu 2.6.9-34.0.2.ELsmp #1 SMP Fri Jun 30 10:33:58 EDT 
2006 i686 i686 i386 GNU/Linux

How reproducible:
We have two servers similarly configured and they both exhibit the same 
behavior.

Steps to Reproduce:
1. Directly attach iscsi device
2. Create an iscsi.conf with a single line containing the DiscoveryAddress of 
the iscsi device.
3. service start iscsi
  
Actual results:
iscsi device works fine
messages logged every ten seconds

Expected results:
iscsi device works fine
no messages


Additional info:
This is more of a nuisance issue since the iscsi device is functioning well. 
The message log just get clogged with these recurring messages.

Comment 2 Michael Will 2007-06-11 00:06:27 UTC
There is a different bug around the forcedeth driver 6.10 losing connectivity
and then the same messages showing up. Reloading the forcedeth driver fixes it
until it reoccurrs. I will file a different bug report for that. 

Comment 3 Mike Christie 2007-06-20 16:27:03 UTC
This should be fixed in RHEL 4.5 when it comes out.

We will now retry the login 3 times, and if we cannot login we will stop
retrying. So you will see a error message for each of the 3 retries, but it will
no longer continue to spew errors and fill up the logs.

Comment 4 Michael Will 2007-06-20 19:16:53 UTC
But it should be retrying if it really lost the connection. 

I read the original bug report as that they have a working connection and get
timeout messages anyways. That would be something to fix if it is really what is
happening. 

However if their iscsi box is just not keeping up with the default protocol
timing then you can adjust them to your liking:

Check out the comments in stock /etc/iscsi.conf that explains LoginTimeout,
IdleTimeout, ActiveTimeout and PingTimeout

Michael Will

Comment 5 Mike Christie 2007-06-20 19:48:30 UTC
(In reply to comment #4)
> But it should be retrying if it really lost the connection. 
> 

The code does. If we had a connection and lost it we continue to retry. We only
limit retries on the initial login if we never get an initial connection.

> I read the original bug report as that they have a working connection and get
> timeout messages anyways. That would be something to fix if it is really what is
> happening. 

I did not read the bug that way and that would not make much sense if they are
also saying the iscsi device works. The problem is that we can log into some
portals and some we cannot get an initial log in to. In RHEL3, we would give up
eventually and in some cases because the driver did failover it was completely
hidden until you tried to failover. In the RHEL4 driver we do not do failover
and the initial login retry limit was accidentally removed.



Comment 6 Tom Fredian 2007-06-20 20:00:27 UTC
Yes, the iscsi device worked just fine with the same configuration with RHEL3
and RHEL4.4 but RHEL4.4 produced the errors in /var/log/messages. We have been
running RHEL4.5 for some time now and the problem has gone away. I would have
reported this but I posted this bug report almost a year ago and there was no
activity on it until now so I completely forgot about it. We lived with the
messages since the iscsi connection still worked fine. In any event, the problem
has gone away with 4.5.

Thanks!