Re: NFSv2 boot & OLD_NFSV2

> On 21. märts 2017, at 10:50, Daniel Braniss <danny_at_cs.huji.ac.il> wrote:
> 
> 
>> On 21 Mar 2017, at 10:13, Baptiste Daroussin <bapt_at_FreeBSD.org <mailto:bapt_at_FreeBSD.org>> wrote:
>> 
>> On Tue, Mar 21, 2017 at 09:58:21AM +0200, Daniel Braniss wrote:
>>> 
>>>> On 20 Mar 2017, at 23:55, Toomas Soome <tsoome_at_me.com <mailto:tsoome_at_me.com>> wrote:
>>>> 
>>>>> 
>>>>> On 20. märts 2017, at 23:53, Rick Macklem <rmacklem_at_uoguelph.ca <mailto:rmacklem_at_uoguelph.ca>> wrote:
>>>>> 
>>>>> Baptiste Daroussin wrote:
>>>>>> On Mon, Mar 20, 2017 at 08:22:12PM +0200, Toomas Soome wrote:
>>>>>>> Hi!
>>>>>>> 
>>>>>>> The current boot code is building NFSv3, with preprocessor conditional OLD_NFSV2. Should NFSv2 code still be kept around or can we burn it?
>>>>>>> 
>>>>>>> rgds,
>>>>>>> toomas
>>>>>> 
>>>>>> I vote burn
>>>>>> 
>>>>>> Bapt
>>>>> I would be happy to see NFSv2 go away. However, depending on how people configure
>>>>> their diskless root fs, they do end up using NFSv2 for their root fs.
>>>>> 
>>>>> Does booting over NFSv3 affect this?
>>>>> 
>>>>> I think the answer is no for a FreeBSD server (since the NFSv2 File Handle is the same as
>>>>> the NFSv3 one, except padded with 0 bytes to 32bytes long).
>>>>> However, there might be non-FreeBSD NFS servers where the NFSv2 file handle is different
>>>>> than the NFSv3 one and for that case, the user would need NFSv2 boot code (or
>>>>> reconfigure their root fs to use NFSv3).
>>>>> 
>>>>> To be honest, I suspect few realize that they are using NFSv2 for their root fs.
>>>>> (They'd see it in a packet trace or via "nfsstat -m", but otherwise they probably
>>>>> think they are using NFSv3 for their root fs.)
>>>>> 
>>>>> rick
>>>> 
>>>> if they do not suspect, they most likely use v3 - due to simple fact that you have to rebuild loader to use NFSv2 - it is compile time option.
>>>> 
>>> 
>>> old systems, 8.x, still use/boot v2, and so do old linux.
>>> NetApp has discontinued support for v2, so we had to move this machines to use FreeBSD server and the day was
>>> saved. So, till these machines get upgraded/discontinued we have a problem. There are several solutions
>>> to this issue, but as long as it's a matter of getting rid for the sake of it, I would vote to keep it a while longer.
>>> 
>>> danny
>>> 
>>> 
>> Given you are speaking of 8.x I suppose you are using the loader that comes with
>> it, meaning you are safe if we remove it from the loader in 12.0 (note as said
>> by Toomas that is it is already off by default in the 12.0 loader) am I missing
>> something?
>> 
> 
> as usual, did not read the whole thread, I assumed - wrongly - that support for v2 would be discontinued.
> removing v2 support from the boot process is fine! great, go for it. It will only involve newer
> hosts, and simplifying the boot process is always a good idea.
> 
> sorry for the noise.
> 	danny
> 


yes, just to clarify,  the current loader code (in current), is having NFS code implemented as:

#ifdef OLD_NFSV2

v2 implementation is here

#else

v3 implementation is here

#endif

Which does mean that pxeboot/loader.efi is built by default to use v3 only, but we do have 2 parallel implementations of the NFS readers. And yes, the question is just about boot loader reader code (we do not implement NFS writes) - and we are *not* talking about server side there.

Indeed it also is possible to merge those 2 version implementations, but to be honest, I see very little point of doing that either, even if there is some setup still with v2 only server, there is still an option just to use TFTP based boot - especially given that current boot loader does provide parallel option to use either NFS or TFTP (via dhcp option 150), with existing binaries - that is, without having to re-compile.

rgds,
toomas