[Discussion] can ROCE protocol work with NAT (Network Address Translation)?

[Discussion] can ROCE protocol work with NAT (Network Address Translation)?

[wangqi]

Dear experts,

    Because of a project, we need to use ROCE to send data from

region A to region B. A and B are not in a same LAN, and it will

go through NAT (Network Address Translation). However, we found

that we can't send data successfully. We do some investigations

and find that in an INTEL ppt, it says because "ICRC doesn't allow

IP header modifications", ROCE protocol can't work with NAT

while iWARP can work with NAT. We want to ask a few questions.

1. Can ROCE protocol work with NAT? Is the INTEL ppt right?

2. Is there any method that we can use to make ROCE work with

NAT? For example, can we modify or remove the ICRC part in the

ROCE protocol? Is it a good idea?

Best wishes,

Qi

Re: [Discussion] can ROCE protocol work with NAT (Network Address Translation)?

[Leon Romanovsky]

On Fri, Jan 10, 2020 at 06:51:39PM +0800, wangqi wrote:
> Dear experts,
>
>     Because of a project, we need to use ROCE to send data from
>
> region A to region B. A and B are not in a same LAN, and it will
>
> go through NAT (Network Address Translation). However, we found
>
> that we can't send data successfully. We do some investigations
>
> and find that in an INTEL ppt, it says because "ICRC doesn't allow
>
> IP header modifications", ROCE protocol can't work with NAT
>
> while iWARP can work with NAT. We want to ask a few questions.
>
> 1. Can ROCE protocol work with NAT? Is the INTEL ppt right?

I have no idea to which "INTEL ppt" you are referring, but RoCEv2
is an extension of RoCEv1 to support routing over different subnets.
Instead of IB GRH field in RoCEv1 packets, RoCEv2 uses IP and UDP
headers.

>
> 2. Is there any method that we can use to make ROCE work with
>
> NAT? For example, can we modify or remove the ICRC part in the
>
> ROCE protocol? Is it a good idea?a

Use proper hardware that supports RoCEv2.

>
> Best wishes,
>
> Qi
>
>