Hi,

Les Mikesell wrote on 31.01.2007 at 23:46:13 [Re: [BackupPC-users] RHEL4 fresh 
load - child exited prematurely]:
> Timothy J. Massey wrote:
> 
> > I've used **3** different computers with wildly different hardware.  On 
> > the host side, I've used **4** different computers (and most of them are 
> > high-end server hardware) with wildly different hardware.  It's not 
> > related to a specific brand or type of hardware.
> 
> But lots of other people including myself run rsync without errors so it 
> has to be something unique to your situation.

well, no. You don't rule out bugs by "it works for me", not even by "it
works for everyone I know". I'm sure you know that.

We don't know much about the "lots of other people", do we? We know there
have been no further *reports* of it on this list, but I don't remember
hundreds of people reporting success with rsync on RHEL4 either. You might
know about other lists, I don't.

That said, I fully agree with you in that

a) I don't suspect an rsync bug and

> That 'no route to host' 
> message isn't coming from rsync - it is a system error that it is 
> reporting.

b) that it's not an application level error. It *could* be caused by the
   application (incorrect setsockopt(), fcntl() or something the like),
   but that's not probable (in my opinion at least).

> Maybe cables from a different vendor would help.

I doubt it, because other applications are doing well. It doesn't seem to be
hardware related to me. I suspect the kernel on the host side (backup client)
or its configuration. Of course, it may be hardware specific in that
different hardware does not trigger whatever is happening (and that could
include the switch, maybe, perhaps), but the cables? It's not the hardware
where I would start looking, especially after Tim *has* tested quite a lot
of different setups.

It could be stupid things like arp poisoning, a misbehaving machine on the
local network or whatever. Remains the question what communication
characteristics rsync has and SMB doesn't (hmm, SMB is UDP, isn't it?) that
make the problem appear.

Tim sent me his /etc/sysctl.conf off-list, and I find it harmless (that
refered to "kernel configuration" before I added the previous paragraph). As I
understand him, he's about to try out different kernels (2.4.x ?), now that
he has a test setup available. Swapping kernels is *not* something I'd happily
do without further thought on a production server either, and I'm sure you
agree.

May I summarize a few points I believe we all agree on?

1.) It's a client side problem, i.e. the backed up client seems to be the
    cause, not the BackupPC server machine.
2.) It is thus not a BackupPC problem. On the client only stock RHEL4
    software is in use (on the test setup anyway).
3.) It is still on-topic in that it happens using BackupPC and only then.
    Other users of BackupPC may run into similar problems and be glad to
    find a solution in the archives once we find one.
4.) It's an obscure and unnerving problem. There are many things to try out,
    nothing obvious springing to mind, and each of us has different thoughts
    on what to try in which order :).

My bet stays the kernel. Craig has a point with the isolated network. Either
one might fix it, without leading to a definitive diagnose. Running on an
isolated network as a workaround is not an option :-), but it's the easier
thing to try out, and *reproducing* the problem on an isolated network would
rule out quite a lot of causes.

The only other idea I have in mind right now is wishing Tim good luck.

Regards,
Holger

-------------------------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier.
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642
_______________________________________________
BackupPC-users mailing list
BackupPC-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/backuppc-users
http://backuppc.sourceforge.net/

Reply via email to