[Lustre-discuss] Understanging LNET routing

[Vsevolod Nikonorov]

Thanks, seems like my router is a router indeed. Nevertheless I am unable to mount Lustre filesystem: "mount.lustre 10.3.0.102 at tcp:/SANDBOX /mnt/lustre" just hangs, though meanwhile Lustre client communicates with Lustre router (which may be seen using rules like "iptables -I INPUT -p tcp ! --dport 22 -j LOG"), and Lustre router communicates with my MDS. /var/log/messages on MDS does not contain a single line about Lustre activity, though mdt volume is formatted and mounted properly. I thing I need to increase debugging level at least on MDS, how can it be done?

On Mon, 19 Aug 2013 14:37:11 -0400
David Dillow <dillowda at ornl.gov> wrote:

> On Mon, 2013-08-19 at 16:50 +0400, Vsevolod Nikonorov wrote:
> > Is it possible to route Lustre traffic between two TCP networks?
> 
> Yes, and you have multiple ways to achieve that goal. If you are using
> TCP, then it routes just like any other IP traffic -- you may not even
> need Lustre routers.
> 
> If you are trying to change LNET types -- say from RDMA over IB to TCP
> -- you would run an LNET router to handle the protocol translation.
> 
> There are other reasons to run LNET routers, such as maintaining
> separation between networks or fabrics, but in many cases those are more
> administrative or performance based than absolute technical
> requirements.
> 
> >  Manual states that
> > 
> > "the routers would enable LNet forwarding since their NIDs are
> > specified in the 'routes' parameters as being routers."
> > 
> > How can I query the router if it consideres itself a router?
> 
> Look in /proc/sys/lnet/routes; if you see "Routing enabled" then the
> router knows it is a router.
> 
> Hope this helps,
> -- 
> Dave Dillow
> National Center for Computational Science
> Oak Ridge National Laboratory
> (865) 241-6602 office
> 
> 


-- 
Всеволод Никоноров,
ОИТТиС, НИКИЭТ

<v.nikonorov at nikiet.ru>