No SAN experience !!

[chaz112182]

Hello,

Relatively new to VI3, ESX, etc and have always managed servers with direct attached storage so please bare with me on this one. My firm will be moving a good portion of our servers to ESX + shared storage in the near future. I have built out a lab using ESX but since we don't have any shared storage on site I still feel like I'm lagging behind a bit. I'm looking for some resources that can help bring me up to speed on shared storage ( right now we are leaning towards iSCSI SAN). Any insight would be greatly appreciated.

[JohnADCO]

You need the san (or some other form of networked centralized storage) because of redundancy.

ESX is cool, with two or more hosts connected to centralized storage you can have a host go down with little to no business interruption.

I did some searching and did not really come up with a good doccument that was SAN -vs- Direct Attached. I will only say we started our virtualization / iSCSI san infrustructure change over project last Oct. and there is no way way I could ever go back to direct attached storage. Scores of advantage san points realized in this small time frame. And we purchased cheapo sans.

[MrBiscuit]

It might be easier if you gave us a view of what you're looking to do with the environment in the immediate and then medium term, from there we could suggest some Vendors/products which would ballpark match your technical needs, and from there perhaps you could engage a partner who take you through a few labs on the equipment. Most vendors are more than happy to put you in a room with one of their pre-sales techs to show you through the paces of their equipment.

Just based on the information you've provided already:

I can tell you that if you're new to SAN technologies in general iSCSI is an easier infrastructure to learn and implement as you are already probably familiar with many parts of it.

You don't have to buy a vendor branded SAN to get shared storage in your lab environment, many people are successfull with putting a bunch of DAS in an auxilliary server and running a software solution from it. Great for learning the ropes and understanding DRS and HA at a fraction of the cost. Sure they're generally not on the supported list, but if you have a look on the forums here there's a few cookbooks on setting one up.

Like I said, a bit more info about your goals and we can probably be more forthcoming.

[Lightbulb]

Also you could throw up an Openfiler (http://www.openfiler.com/) system for ues in you LAB. This will give you experience with ISCSI for little cost.

[Texiwill]

Hello,

Your shared storage can be a FC-SAN ($$$) and iSCSI SAN or an NFS v3 over TCP server.

iSCSI and NFS could be provided by Windows, Linux, FreeBSD, etc. There is also OpenFiler and FreeNAS.

If you rather make use of your 'local' storage as shared storage investigate HP Lefthand Networks VSA and Xtravirt's XVS.

There are many free or inexpensive options available to you.

Best regards,
Edward L. Haletky
VMware Communities User Moderator, VMware vExpert 2009
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

[chaz112182]

thank you for all the responses and great information. i really appreciate it. i just acquired a demo copy of lefthand networks vsa so im going to try and fill an auxiliary server (as mr biscuit suggested) with das and then install the vsa software. i'm assuming that i can just use any old switch (i.e. netgear 5 port unmanaged) to create the storage network ? one other question i have is how is performance affected when using shared storage ? johnADCO i know you mentioned that you wouldn't ever go back to das, is this strictly because of the redundancy shared storage provides, or did you also see performance increase ? again thanks for all the helpful information and i look forward to hearing from you again.

[chaz112182]

in terms of immediate plans all of the servers running our time & billing applications and our document management system are coming off of lease in about 6 months. both are considered critical applications. the time/billing servers are heavily underutilized as are the dms servers (with the exception of the indexer). the dms consists of seven servers (two that act as brokers that handle all client requests, a file server, an index server, a sql server, a web server, and a workspace manager server).

[MrBiscuit]

In a lab environment, any switching device is acceptable (no hubs tho!) if you are using old or unmanaged equipment I would strongly recommend that you use a seperate device for storage traffic to comms traffic.

In terms of performance, and I'm really generalising here, a SAN will employ a much higher quality of disk, controller and software which results in better performance, reliability and management. You also typically gain features you'll never know how you did without like snapshots, replication and the like. Just consider at a basic level that a SAN is probably spreading your workload over more spindles, which is the most basic method of increasing disk performance.

Just as a side point, you don't have to abandon DAS - several vendors produce tools to allow their SAN technology to interact with common DAS solutions, of particular note to a smaller environment is NetApp.

[JohnADCO]

Interesting about the performance gains. You know, iSCSI doesn't really give you the wow numbers on raw disk performance tests that DAS can. But, in production, everybody (Users) has commented on how the system is faster now, some admin operations are 10 times faster, some large backups were cut in half. We run about 12 vm's per host, three hosts. We have had as many as 24 VM's running on a single host during maintance windows, performance seems impressive on our high rpm sas equipped sans, I'd lable it as acceptable on our SATA equipped sans.

I mean, I have several large store's. It was utterly rediculous attempting to move them around using any conventional tools with direct attached storage. I mean I can get a full disk copy of my largest store in a couple a three hours now. And that is a copy I can map a Host / VM to and run on, no restores involved.

I can test virtually endlessly now without interrupting any up time.

I can fully manage the health of my storage in one place.

And growth is a piece of cake, well up to the 45TB limit of the SANs I purchased anyways.

I now just consider it the right tool for the job.

[JohnADCO]

You certainly seem ripe for virtualization.....

[chaz112182]

i have 2 esx hosts setup w/ a vsa vm on each. i am running into a problem, however, with the networking.

each host has two nics. when i went through the initial esx installations i configured the first nics with a static ip

for service console on our production network so i could manage them using the virtual infrastructure client on my laptop.

i have the secondary nics plugged into a netgear switch and have created a vswitch with a vm port group, vmkernel port group, etc.

the problem is i can't seem to configure the secondary nics w/ and ip, subnet, etc. if i do a esxconfig-nics -l this is what i get:

# esxcfg-nics -l

Name PCI Driver Link Speed Duplex MTU Description

vmnic0 03:00.00 bnx2 Up 1000Mbps Full 1500 Broadcom Corporation Broadcom NetXtreme II BCM5708 1000Base-T

vmnic1 05:00.00 bnx2 Up 100Mbps Full 1500 Broadcom Corporation Broadcom NetXtreme II BCM5708 1000Base-T

but when i do esxconfig-vswif i get:

# esxcfg-vswif -l

Name Port Group IP Address Netmask Broadcast Enabled DHCP

vswif0 Service Console 192.168.10.34 255.255.255.0 192.168.10.255 true false

also attached is a screen shot of my networking configurtion from the infrastructure client. any sight would be very, very helpful !!

[Texiwill · Accepted solution]

Hello,

VSA is an iSCSI server so you need to make sure your service console and vmkernel iSCSI port can both reach the VSA appliance. Basically I would take your two pNICS, team them together and use VLANs to segment out only your VM non-VSA traffic. Not quite secure, for that you may need more pNIC.

Best regards,
Edward L. Haletky
VMware Communities User Moderator, VMware vExpert 2009
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

[chaz112182]

just wanted to say thanks to all who contributed to this post I was able to get my VSA lab configured and working properly with your help !!