Re: [virtio-comment] [PATCH v4 4/7] transport-fabrics: introduce command set

> On Jul 30, 2023, at 10:34 PM, zhenwei pi <> wrote:
> 
> 
> 
> On 7/30/23 07:28, Raphael Norwitz wrote:
>> As noted in my high level feedback I think the protocol should have redirection semantics.
> [snip]
>>> +\end{lstlisting}
>>> +
>>> +\paragraph{Connect Command}\label{sec:Virtio Transport Options / Virtio Over Fabrics / Commands Definition / Opcodes / Connect Command}
>>> +
>> This would be a good place to introduce some kind of target-side redirect mechanism to support redirecting to another IP.
>> Probably just another op/status code and message from the target for redirection?
> 
> Redirect mechanism is not used widely in my practice. Instead, multi path mechanism is used a lot. Would you please share your experience on this?
> 

Agreed - multipath is more common in iSCSI implementations. How would you make multipath work for Virtio-o-F since you only have one TCP or RDMA connection per VQ?

What concern do you have with redirection-based iSCSI implementations? Itâs conceptually quite trivial. We have published documentation on our implementation here: https://www.nutanixbible.com/5b-book-of-ahv-how-it-works.html .

I imagine Virtio-oF implementations could do something similar to avoid reliance on a fixed IP. 

> -- 
> zhenwei pi