[Linux-HA] Spurious serial write timeouts

[Mike Dahmus]

On Wed, 2004-03-24 at 10:53, Alan Robertson wrote:
> Mike Dahmus wrote:
> > On Wed, 2004-03-24 at 10:18, Alan Robertson wrote:
> > 
> >>Mike Dahmus wrote:
> >>
> >>>We're prototyping a two-machine cluster whose sole purpose is to serve
> >>>one IP address. They're connected right now over a serial cable at 9600+
> >>>baud (I've tried various speeds) with all of the expected signals on the
> >>>cable (output below). I'm getting intermittent spurious serial write
> >>>timeouts and am curious if anybody has any additional debugging
> >>>suggestions (archives indicated to run heartbeat with various debugging
> >>>flags which I've been unable to locate as of yet).
> >>>
> >>>heartbeat: 2004/03/24_08:59:05 WARN: TTY write timeout on [/dev/ttyS0]
> >>>(no connection or bad cable? [see documentation])
> >>>
> >>>Both machines are running variants of 2.4.20 kernel.
> >>
> >>What version of heartbeat are you running?  Red Hat put out some buggy 
> >>2.4.20 kernels...   And, when you say "intermittent spurious", how often 
> >>does this occur?
> > 
> > 
> > Hi Alan,
> > 
> > heartbeat is heartbeat-1.2.0-1.rh.9
> > 
> > And "intermittent" means it usually happens relatively soon after
> > startup but not always. 
> 
> OK...  Does it occur afterwards?  Like once an hour?  [the message normally 
> won't come out any more often than once an hour]

I'll let it keep running. Here's the debug output after I sent a bunch
of signals (I saw the timeout in ha-log and have attached the debugging
output from the same period in time) - note 10:53:36 was when the main
log reported the write timeout.

heartbeat: 2004/03/24_10:53:28 debug: >>>
heartbeat: 2004/03/24_10:53:28 debug: serial write returned 129
heartbeat: 2004/03/24_10:53:30 debug: Sending pkt to /dev/ttyS0 [129
bytes]
heartbeat: 2004/03/24_10:53:30 debug: >>>
heartbeat: 2004/03/24_10:53:30 debug: serial write returned 129
heartbeat: 2004/03/24_10:53:32 debug: Sending pkt to /dev/ttyS0 [129
bytes]
heartbeat: 2004/03/24_10:53:32 debug: >>>
heartbeat: 2004/03/24_10:53:32 debug: serial write returned 129
heartbeat: 2004/03/24_10:53:34 debug: Sending pkt to /dev/ttyS0 [129
bytes]
heartbeat: 2004/03/24_10:53:34 debug: >>>
heartbeat: 2004/03/24_10:53:34 debug: serial write returned 129
heartbeat: 2004/03/24_10:53:36 debug: Sending pkt to /dev/ttyS0 [128
bytes]
heartbeat: 2004/03/24_10:53:36 debug: >>>
heartbeat: 2004/03/24_10:53:36 debug: serial write returned 120
heartbeat: 2004/03/24_10:53:38 debug: Sending pkt to /dev/ttyS0 [129
bytes]
heartbeat: 2004/03/24_10:53:38 debug: >>>
heartbeat: 2004/03/24_10:53:38 debug: serial write returned 129
heartbeat: 2004/03/24_10:53:40 debug: Sending pkt to /dev/ttyS0 [129
bytes]
heartbeat: 2004/03/24_10:53:40 debug: >>>

Regards,
Mike