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<tt>On 10/12/2011 3:28 PM, richard Croucher wrote:</tt>
<blockquote cite="mid:1318426108.3206.30.camel@vaio-linux"
type="cite"><tt>
I understand that's it not good practice however I'm seeking to
understand whether actual problems have been observed. </tt>
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<tt><br>
<br>
The only issues I can suggest will be because of ARP is in the
shared broadcast domain. Is there any IPoIB state in the SM
other than QoS? I can't think of any reason why there should
be. Even though ARP requests will be seen by interfaces in a
different subnet, they should not respond with it's GUID since
they will not match the requested IP address.<br>
</tt></blockquote>
<tt><br>
wrong, see
<a class="moz-txt-link-freetext" href="http://lxr.linux.no/#linux+v3.0/Documentation/networking/ip-sysctl.txt#L926">http://lxr.linux.no/#linux+v3.0/Documentation/networking/ip-sysctl.txt#L926</a><br>
<br>
</tt>
<blockquote cite="mid:1318426108.3206.30.camel@vaio-linux"
type="cite"><tt>
<br>
I think this refers back to behaviour seen many years ago, when
multihomed hosts were rare. There was a tendency for them to
respond on all interfaces to ARP requests for their nodename
and cause ARP resolution problems.. Is there a reproducable
test case of this problem, since I certainly know of systems
which are configured like this and appear to be working fine.
Maybe, they've just been lucky, but so far I've seen numerous
messages saying don't do it and none to say what actually goes
wrong. <br>
</tt></blockquote>
<tt><br>
For basic testing and/or PoC you can set
net.ipv4.conf.*.arp_ignore to 1 or alike (2). For production, I
wouldn't<br>
do that or at least do it after conducting a deeper study (I gave
you the heads-up, so please share your findings...),<br>
Indeed, I know that in the iscsi multipathing world people use
multi-homed NICs on the same IP subne, though. <br>
<br>
Or.<br>
<br>
</tt><tt><br>
</tt>
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