CISCO UCS Functionnalities

jskfan
jskfan used Ask the Experts™
on
I have done some reading about CISCO UCS.
To my initial understanding it is just a Blade server , like other traditional blades such as DELL, HPP,  etc.. but with less wires to run in the Rack.
However when I started reading about its capabilities of booting from the SAN , then Service profiles, for now it is a little bit confusing.

If I understand  each blade is one computer with hard disk, memory, cpu, etc... and on each blade  you can install one operating system, such as Windows.
So why would they make it boot from the SAN, and why they create service profile, Pools,..

I have dealt with traditional blades, but cannot understand the functionalities of UCS.

Thanks
Comment
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
Rodney BarnhardtServer Administrator
Commented:
I think you are just getting confused because of the versatility and configuration options. The UCS has anywhere from two to eight 10G link up to the fabric interconnect. These allow for all communications network, fiber, etc. The service profiles are a way to pre-configure a blade with specifics such as the number of virtual NIC's, HBA's, etc. This makes provisioning much simpler. We do boot from SAN in our environment. However, you could also install drives on the blade and install and OS on the blade directly if you so choose. It all depends on someone's preference.

Author

Commented:
I know that VMware VMs are in the SAN and get booted from the SAN.
I am not sure if UCS is set up the same. If so do the UCS blades have some type of Hypervisor like VMware has ESXi ?

You see where I get confused
 where does the UCS Stand?. Is it blade server like HP and Dell blade servers, with simplified wired?
is UCS SAN storage Manager ?
is it both as blade server as well kind of  SAN(Iscsi initiator) ?
Rodney BarnhardtServer Administrator

Commented:
No, they do not have an integrated hypervisor. I am not sure if you can get a blade with it embedded or not. Basically, at least the way we did ours, you map to a LUN on the storage side, ensuring that LUN is given a LUN ID of 0 making it the boot LUN. Then, in the UCS console you can mount the ISO to the blade and install the OS that way. This is the process we used to install ESXi on our blades.

As far as wiring, I am not positive. The only experience I have with other blades was a few years ago. HP gave use a free chassis with two blades at the same time we implemented our first UCS chassis. They were trying to convince us to go with them. However, even with HP support, it took nearly a month to get the HP to communicate correctly with our EMC storage. I do know we currently only use two 10G CNA links per chassis to our fabric interconnect switches, so the cabling seems simpler.

I would not call UCS a storage manager. However, Cicso is working with a vSAN type environment, I have not tried it or heard anything about it. However, it can act as a SCSI initiator if the profile is configured for it.
I hope this helps.
Should you be charging more for IT Services?

Do you wonder if your IT business is truly profitable or if you should raise your prices? Learn how to calculate your overhead burden using our free interactive tool and use it to determine the right price for your IT services. Start calculating Now!

Author

Commented:
I see …
 Booting from SAN is still dark area…

If I have Windows OS on a blade already installed, why would I boot it from the SAN ? does it mean the OS on the blade will not be used ?
Rodney BarnhardtServer Administrator

Commented:
We bought our blades diskless, which is why we boot from SAN. However, if you have local storage on the blades and would like to have an OS such as ESX, Windows, Hyper-V, etc you can do that if you would like.
Top Expert 2014

Commented:
ESX hardly warrants boot from SAN since it fits on an SD card.

Not sure how Cisco can claim less wires, they can't get more than 10Gb over a 10Gb cable so if you need 100Gb to the enclosure you need 10 x 10Gb Ethernet cables with them same as the rest. Maybe it's because they're pushing convergent networking (TCP/IP plus Fibre Channel over Ethernet) but others also have IP/FCoE offerings. Probably comparing a traditional HP blade with 2 onboard NICs for IP plus a fibre channel Mezzanine against an onboard convergent networking NIC - that would be less cables to the enclosure but the downside is you're tied to buying a hugely expensive Cisco Nexus switch plus FC module and FC licenses. You're also pretty much tied to Cisco TAC for support either direct or through a partner, the people we get HP/Dell/IBM parts from won't even sell us generic RAM if we tell them it's for a Cisco UCS.

Server profiles facilitate rip/replace, you can have a spare blade in the enclosure and if one dies you push the profile of the failed one to it and if it's boot from SAN it'll boot up and run just like the original, but HP can do that with Virtual Connect and others have similar solutions. Hardly worth having for VMware since you would have a HA cluster anyway.

Author

Commented:
When they say boot from the SAN.
DOes that mean the CPU and Memory will still be the ones on the blade, and only the disk where the OS is contained is on the SAN  will be used

I do not see the purpose of booting from the SAN , other than the ability to provision more disk space than what the disk on the blade is able to.
Rodney BarnhardtServer Administrator

Commented:
Yes, the blade memory and CPU is used and the SAN is used for disk. In our case, we already had a robust SAN and therefore bought diskless blades.
Top Expert 2014
Commented:
Boot from SAN gives you the ability to replace a server with another one without physically touching it. Say the smoke leaks out of one server, you re-map the LUNs to another server and power that on and it runs whatever OS and software the blown up one was running. Of course without Boot from SAN you could go to the machine and swap the boot disks across to achieve the same result but maybe the servers aren't physically accessible.

Author

Commented:
Thank you very much Guys!

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial