It works just like aoe_deadsecs, example: echo '4' > /sys/module/aoe/parameters/aoe_helpsecs
The logic behind the patch example...In an mpio situation we could have one target advertised through two network interfaces eth0 and eth1. eth0 is connected to switch0 and eth1 is connected to switch1. The initiator also has two interfaces, eth0 using switch0 and eth1 using switch1.
In the event of a failure on a single switch, the initiator will either down the device due to aoe_deadsecs or try another target when hitting HELPWAIT (old, now defined as aoe_helpsecs). In normal mpio operation, traffic will flow through eth0 and eth1 on both the target and initiator. To reduce the wait time and path failure detection, setting aoe_helpsecs to a smaller value will ease the transition with automatic failover/failback. In doing so, aoe_deadsecs will not be reached and no errors should occur.
The patch has been generated from a vanilla kernel.org linux-2.6.26.8 kernel and has shown to work on 2.6.28.1 also (thats all I have tested). I looked through the source code for the driver from coraids site and see that somewhere along the lines HELPWAIT was abandoned but no reason why (or if its handled in another manner - doesn't seem to be from testing). I would propose adding this back in since it seems vital for this type of setup.
-- Matth Ingersoll
linux-aoe-helpsecs.diff
Description: Binary data
------------------------------------------------------------------------------ Apps built with the Adobe(R) Flex(R) framework and Flex Builder(TM) are powering Web 2.0 with engaging, cross-platform capabilities. Quickly and easily build your RIAs with Flex Builder, the Eclipse(TM)based development software that enables intelligent coding and step-through debugging. Download the free 60 day trial. http://p.sf.net/sfu/www-adobe-com
_______________________________________________ Aoetools-discuss mailing list Aoetools-discuss@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/aoetools-discuss
