[pve-devel] Integration of FreeNAS iSCSI target initiator in Proxmox Enterprise repo

[bsd at todoo.biz]

> Le 3 juin 2020 à 12:03, Michael Rasmussen <mir at datanom.net> a écrit :
> 
> Signé partie PGP
> On Wed, 3 Jun 2020 11:34:35 +0200
> Andreas Steinel <a.steinel at gmail.com> wrote:
> 
>> 
>> If I remember correctly, the problem with the ZFS-over-iSCSI stuff is
>> that the backend provider in FreeNAS/FreeBSD has changed numerous
>> times and at least one version did not support online
>> reconfiguration. That may be solved right now, but I haven't look at
>> the plugin for a long time. It just works for Debian as Mario
>> (@fireon) described in [2].
>> 
> 
> A few years ago the FreeNAS API was fluctuating between every new minor
> release (eg, 9.3 -> 9.4) and was as such called 'not production ready'
> by IXSystems and therefore labelled beta, experimental etc (I know that
> no product developed by Alfabet (google) never has transitioned from
> beta to production state ;-) This means that maintaining such a plugin
> is very time consuming and since this is bade in peoples free time
> there likely will be the same resources required to do that.

A lot of time has passed since version 9 of FreeBSD / FreeNAS. Six years to be precise. 

iSCSI on FreeBSD is used by very large corporation (Gandi  not to name them https://www.gandi.net/en <https://www.gandi.net/en> is hosting all it's VM using FreeBSD + Linux on the initiator side) with an excellent level of stability. 

Solution derivated from Illumos are either overpriced, closed source and scarcely used or abandoned (if not all at the same time). 

I think that It might be time to re-considering FreeBSD as a potential stable solution to host iSCSI targets. 
Considering the very important efforts FreeBSD has made to implement ZFS and stick to the OpenZFS standards. 

> On the
> other hands those plugin already present in Proxmox uses production
> stamped solutions which rarely/ever makes breaking changes is more
> likely to be maintainable in peoples free time. As a side note: The
> current iscsi initiator (ctld) in FreeBSD still has an upper limit of
> 1024 LUNs per target so therefore qualifies as an plugin alternative to
> proxmox
> 
> #define MAX_LUNS 1024 [0]
> 
> [0] https://github.com/freebsd/freebsd/blob/master/usr.sbin/ctld/ctld.h

This is not true. 

The limit that you are mentioning here has been overridden by a tunable parameter. 
https://www.freebsd.org/cgi/man.cgi?query=ctl&sektion=4 <https://www.freebsd.org/cgi/man.cgi?query=ctl&sektion=4>

> TUNABLE	VARIABLES <https://www.freebsd.org/cgi/man.cgi?query=ctl&sektion=4#end>
>      The following variables are available as loader(8) <https://www.freebsd.org/cgi/man.cgi?query=loader&sektion=8&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports>	tunables:
> 
>      kern.cam.ctl.max_luns
> 	     Specifies the maximum number of LUNs we support, must be a	power
> 	     of	2.  The	default	value is 1024.
It turns out that this patch has been developed by one of my fellow developer couple of years ago to bypass the limitations of 1024 LUNs that you mentioned. 

So It should qualify to be selected as an enterprise grade solution to host iSCSI target. 

The fact that some developers are patching Proxmox code to allow *BSD / FreeNAS to perform is a sign that there might have a need for such tool. 

So beside this max luns problem, what else seems to be causing problem with the BSD target ? 


Sincerely yours. 

> 
> -- 
> Hilsen/Regards
> Michael Rasmussen
> 
> Get my public GnuPG keys:
> michael <at> rasmussen <dot> cc
> https://pgp.key-server.io/pks/lookup?search=0xD3C9A00E
> mir <at> datanom <dot> net
> https://pgp.key-server.io/pks/lookup?search=0xE501F51C
> mir <at> miras <dot> org
> https://pgp.key-server.io/pks/lookup?search=0xE3E80917
> --------------------------------------------------------------
> /usr/games/fortune -es says:
> Youth doesn't excuse everything.
> 		-- Dr. Janice Lester (in Kirk's body), "Turnabout
> Intruder", stardate 5928.5.
> 
> 

---
ToDoo - osnet.eu - DynFi.com 
6 rue Montmartre - 75001 Paris
bsd at todoo.biz
web: https://www.dynfi.com
PGP_ID: 0x1BA3C2FD