On Thu, Feb 07, 2008 at 01:56:32PM +0100, Hannes Reinecke wrote: > The problem we're facing here is due to network routing in the > connected switches. When using static IP addresses the switch has > to set-up the route from the initiator to the requested target using > the tree-spanning algorithm. This will take some time to setup, > during which any connect() attempt from the initiator will fail with > -EHOSTUNREACH. > > But as the in-kernel iSCSI tcp code is essentially stateless, it > cannot differentiate between failures upon startup (where > EHOSTUNREACH might be retried) and real failures during normal > operations (where EHOSTUNREACH is indeed a critical failure). > > Note, this is while the network card has signalled the network is > up, as from the POV of the card it is. > > We could circumvent this by pinging a target marked as automatic > upon startup, but of course this will fail if no targets are > configured ... > > So this a real bugger. And I have no idea how to solve it properly. > > That's why I'm using DHCP. There the routes are already setup as the > DHCP reply somehow has to find its way back to the initiator ...
Fortunately, I am a spanning-tree protocol guru :-) On the switchports that face your hosts and targets but *not* on the switchports that face other switches, you want to enable a few common but not-quite standard features. 1) Port-fast: enabled the port to go straight to the forwarding state 2) BPDU-guard: immediately shutdown the port if STP BPDUs are detected. You need #2 with #1 because #1 allows the creation of transient loops. #2 helps prevent that. In Cisco speak: interface gi0/1 spanning-tree bpduguard enable spanning-tree portfast In HP Procurve speak (need to be running recent firmware): spanning-tree ethernet 10 bpdu-protection spanning-tree ethernet 10 admin-edge-port (for RSTP networks) spanning-tree ethernet 10 mode fast (for classic STP networks) This will eliminate the thirty second waiting period for a port to transition to forwarding. -- Ross Vandegrift [EMAIL PROTECTED] "The good Christian should beware of mathematicians, and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of Hell." --St. Augustine, De Genesi ad Litteram, Book II, xviii, 37 --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/open-iscsi -~----------~----~----~----~------~----~------~--~---