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<font size=3>At 09:16 AM 9/25/2004, Roland Dreier wrote:<br>
<blockquote type=cite class=cite cite=""> Michael> I
would have thought this would be part of the IP over IB<br>
Michael> driver. Communicate with the SM to
acquire the P_Key and<br>
Michael> then use that to perform Arp / ND.
Strange to require a<br>
Michael> command since this gets a bit cumbersome
when there are<br>
Michael> many nodes in the fabric.<br><br>
That is a nice idea in theory but it falls down in practice.
First,<br>
the IPoIB driver is often loaded during the boot process, and init<br>
scripts may want to configure IPoIB interfaces before the SM has<br>
discovered the local node. </font></blockquote><br>
If the SM isn't up or hasn't discovered the local node, then the node
isn't going to be communicating with anything else until this
occurs. To get around this race condition, one simply has an event
handler associated with the change in state of the CA, i.e. the SM has
configured the CA so there is a clear communication path and P_Key can be
discovered. A CA should know when the link is operational as it
needs to find the other routing information in order to operate.
Hence, boot isn't really an issue if using the IB management methods
provided in the specifications.<br><br>
Note: There is nothing that prevents with using a default P_Key (same
applies to Q_Key) - that wasn't the point. <br><br>
<blockquote type=cite class=cite cite=""><font size=3> Also, a node
may have many P_Keys assigned, only a few of which are used for IP
traffic. Administrators<br>
don't like to have to deal with 50+ network
devices.</font></blockquote><br>
What does this have to do with anything? I'm not advocating having
a large number of P_Key for IP traffic. The SM manages the P_Key
space for IP - can be single P_Key or multiple. The SM has to
understand whether a CA is part of a given P_Key domain (same for switch
ports). This is a single point of management technology to start
with so I don't see the 50+ or even 48K network device problem. The
IPoverIB spec allows for multiple P_Key to be used or just one.
This should all be done by the SM and the CA should be asking it for what
value to use. It should not be done within the CA else the
implementation is establishing management policies that were clearly not
the intent of the IB specifications and could to interoperability
problems or more administrative overheads.<br><br>
<font size=3>Mike<br>
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