On Fri, Jul 31, 2009 at 9:43 AM, Ulrich Windl<ulrich.wi...@rz.uni-regensburg.de> wrote: > > On 30 Jul 2009 at 19:25, Erez Zilber wrote: > >> >> Mike, >> >> I'm seeing some strange behavior that I don't completely understand: >> during heavy IO, I disconnect the cable on the target machine and >> after a few seconds, I'm trying to logout from that target on the >> initiator side. Here's what I see: > > Hi, > > IMHO unpluggin the cable is a bad thing to test for network problems: > > 1) A Gb NIC typically takes up to 5 seconds to re-establish the link to a > switch > after re-plugging. > 2) The kernel (udev) may trigger the execution of some scripts to set up the > network after un-plug/re-plug (maybe even using DHCP) > 3) The TCP stack may suspend I/O until some timeout > ...then come the iSCSI issues... > > Maybe a more effective (and easier to manage) test would be adding a blackhole > route. That's purely software and it just makes the packets go to nowhere. >
I'm not trying to test network problems. I'm trying to test real life problems: a computer is connected in the lab and suddenly someone pulls out the cable accidentally or the switch fails etc. Erez --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to open-iscsi@googlegroups.com To unsubscribe from this group, send email to open-iscsi+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/open-iscsi -~----------~----~----~----~------~----~------~--~---