[Linux-cluster] iSCSI GFS

[isplist at logicore.net]

It would be nice to have another path to try before investing in additional FC 
equipment. I also happen to have a Cisco 5420 iSCSI router if it could be put 
to use. I bought it some time ago to give SCSI over IP a try but never got 
around to it. I found the idea interesting but it was fairly new at the time. 
Must be an awful lot of cool solutions now. 

> If you need the ultimate flexibility, you could always have all the
> storage exported via iSCSI to an aggregator box, have that run a
> software RAID to link them all up, and then re-export that via iSCSI.

I need the ultimate because I'm just one guy, trying to take on way too much 
and trying to learn everything I'm touching, at least enough to make it work 
and manage it. Some day, I hope to hire someone to help me out :). 

So, this does sound interesting. 

I'm looking on goggle, I'm not finding exactly what this is yet. Would this 
also be known as storage aggregation or since we're talking about iSCSI, iSCSI 
storage virtualization?

I am guessing that what you're talking about would mean something like the 
servers looking at one point for their data. That one point would be called 
the agregator. 

The aggregator would basically either be the central connection point to all 
of the data (which I doubt since it means it would bog down at some point) or 
it acts as the routing point, sending the server to the proper storage device. 

I am guessing that the storage device ends up being almost anything reachable 
on the network, iSCSI, FC, what ever servers can reach. It might be storage on 
the FC network, it might be a box with an IP, it might be storage behind 
another server.

Is this the idea?

> It rather depends on what your requirements and constraints are. You can
> do all sorts of clever things with a multi-level-tree organisational
> design of your storage solution (something like having a separate
> eggregation box as I described above), and it'll scale pretty much as
> far as you want it. Just add an additional disk chassis into the aggregator.

My concern is also trying to keep things fairly easy to understand so that I 
can explain it to the person that will be hired to help me eventually :). 

More than anything, right now at least, I just want fast reliable LAMP 
services and badly need an easy storage growth path that does not tie me into 
strict requirements. 

Right now, I'm basically married to FC unless I find some alternatives. I 
don't have a problem using FC, I love it, but I'd like to be able to take 
advantage of IP based protocols too.

Mike