[ofa-general] Setting mtu on an IB port

[Mike Aho]

Pradeep,

Thank you, that works well on one machine.  I was able to set the mtu on
interface ib1 to 4096 instead of 2044.  The max_mtu from ibv_devinfo is
still 2048 on port 2.
On the other machine, setting the ip mtu fails if I try a number higher
than 2044.  So which one is the correct behavior?  By the way, opensmd is
running on the other machine.

I appreciate having the capability to do ip mtu and now have another
command in my arsenal.

I was hoping to set the IB mtu to 4096 instead of 2048 as shown in the
ibv_devinfo.  Any ideas on that?

Best Regards,

Mike  Aho




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  |Pradeep Satyanarayana <pradeeps at linux.vnet.ibm.com>                                                                                               |
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  |Mike Aho/Rochester/IBM at IBMUS                                                                                                                      |
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  |OpenFabrics General <general at lists.openfabrics.org>                                                                                               |
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  |06/10/2009 02:20 PM                                                                                                                               |
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  |Re: [ofa-general] Setting mtu on an IB port                                                                                                       |
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Mike Aho wrote:
>
> Is there a way to set the mtu on an IB port?  Thanks.  --Mike
>
>
Mike, you can use "ip link set ib0 mtu <MTU>" for ib0

Pradeep