Hi Paul, > I'd enabled hardware flow control (as Steffen Grunewald had described > on the ipmitool list, thanks Steffen!)
I can't remember the exact kernel internals logic/reason, but I believe if hardware flow control is turned on, the kernel will spin(?) (atleast eat up a lot of cycles) waiting for the ability to dump data out the console. We've only seen this with normal serial connections, but it wouldn't surprise me if the same applied for SOL. If the above case happend, it would suggest ipmitool wasn't capable of handling the SOL traffic quickly enough. That's unlikely. But as you said, perhaps things haven't been stress tested. A few UDP packets lost here and there on the network and ipmitool not ack-ing SOL packets outside of a certain sequence number range could probably cause it. (Note, I don't know the internal logic of ipmitool for this example, its just an idea.) > Has anyone else done any "stress" testing and seen a BMC just fall > down? Never to the degree that you've stated. Although there are situations I can imagine where it can happen. For example, if the maximum number of Lan sessions were alive and connected to the BMC (presumably in background/sleeping processes you weren't aware of it), then the BMC could be out of resources and may not respond to additional traffic. But that's just a guess. A fun black-magic trick I found with some "locked up" BMCs was to simultaneously ping the node w/ rmcp and ipmi at the same time. For some magical reason, this "unlocked" some BMCs for me. I use 'rmcpping' and 'ipmiping' which are in the FreeIPMI project. Al -- Albert Chu [EMAIL PROTECTED] 925-422-5311 Computer Scientist High Performance Systems Division Lawrence Livermore National Laboratory ----- Original Message ----- From: Paul Armor <[EMAIL PROTECTED]> Date: Monday, March 27, 2006 10:12 am Subject: [Ipmitool-devel] SOL connection issue, BMC "locked up" > Hi, > > Sorry for posting to both lists. I have encountered a problem, > whose > source I'm not sure of. This occured on a SuperMicro 1UIPMI-B in > an > H8SSL-i. The system was running a 2.6.15-4 kernel. > > I encountered a problem with an SOL connection that I'm thinking is > either > a problem with the BMC firmware or the openipmi driver (or both?). > The > error below came after some number of hours of the SOL being locked > up. I > was using ipmitool version 1.8.6, checked out of cvs on Feb 24. > > I'd enabled hardware flow control (as Steffen Grunewald had > described on > the ipmitool list, thanks Steffen!), and had logged in over SOL, > and left > a "while true ; do find /usr ; done" over the weekend. I noticed > on > Sunday the console was frozen, and then on Mon morn I found: > > Error sending SOL data: FAIL > SOL session closed by BMC > > and the BMC was no longer on the net... I couldn't even ping it. I > didn't > think to try to openipmi interface to see if the entire BMC fell > down, or > if it just fell off the net. The machine also wouldn't shut down; > agetty > never realised the remote console was gone, and my find process was > happily sleeping: once I'd killed it, the machine happily shut > down. I'm > currently trying to reproduce. > > Has anyone else done any "stress" testing and seen a BMC just fall > down? > Do any openipmi developers have any pointers on where to look to > see > what's hung up? Any thoughts on how to tell if this is a software > problem > or a firmware problem? > > Can any ipmitool developers (Hi Duncan!) offer any thoughts (I > know, I > didn't give you a whole lot to go on)? From ipmitools view, the > host just > went away? > > Thanks! > Paul > > > ------------------------------------------------------- > This SF.Net email is sponsored by xPML, a groundbreaking scripting > languagethat extends applications into web and mobile media. Attend > the live webcast > and join the prime developer group breaking into this new coding > territory!http://sel.as- > us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642_______________________________________________ > Ipmitool-devel mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/ipmitool-devel > ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Openipmi-developer mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openipmi-developer
