What is Converged Infrastructure?

In this post we are going to deal with "What is Converged Infrastructure?" in later posts I'll be looking at the various companies doing the "How to?". The short answer is the unification of the infrastructure - HW and SW, but I think it leads to alot more (although it starts with the physcial infrastructure).

Lets take a look at the back of a rack in a typical data center, do you recognise this picture?

DSCN0123
Originally uploaded by alonzoD

The traditional Data Center Server has multiple physical connections to the LAN carrying ILO (integrated lights out), backup, management, user access and much more. Typically these would vary from 100MB for Management to maybe 1GB for backup.

In addition you might have redudant connections for some or all of these connections. So you might have any where from 2 LAN (test/development server) to upwards of 8 LAN connections if you want to have a highly redudant (production) server. Now look at the picture again, how many servers can you get in a 42U rack? well it depends 1U/2U/4U servers are not uncommon.

Lets use a 4U server in a 42U rack and do some sums, lets say the rack has maybe 8/9 servers (we will use 8 ) and maybe a ToR (Top of Rack) switch, each server with multiple NICS and multiple LAN cables.

Per Rack LAN cabling

8 Servers x 5 cables (1 mgmt, 1 backup, 1 ILO and 2 User Access) = 40 cables.
Each server has 2 x 1 Port HBA for fibre connection to the SAN

Per Rack SAN cabling

8 x 2 = 16 cables for SAN

Total cables for 1 rack = 56 (not including power or cables for uplink connection to Core Network / SAN fabric)

Then you can multiply that across multiple racks. The effects of all these physical cards/cables:-

Power requirement increased
Restricted airflow
Cabling management nightmare (labeling!!!)

Now consider the management (via tools) of physical infrastructure:-

LAN switch ports
VLAN management
SAN Switch ports
SAN Zoning

Using individual management tools - that is (potentially) alot of management (alot of people).

So what is Converged Infrastructure (IMHO)?

Convergence of the physical items - using techniques to reduce physical items

- Virtualized Servers - VMware, Xen, Hyper-v to reduce physical servers
- Virtualized Network - vSwitch, vNetwork Distributed Switch, Nexus 1000v
- Virtualized Storage - Thin provisioning
- FCoE / DCE - using converged network adaptors that carry both Fibre and LAN traffic on the same physical cable - 2:1 reduction in cabling
- SR-IOV - PCI-e adapter that appears to the OS as multiple adapters

Convergence of Mgmt - using

- A single pane of glass managment tool for Server, Storage and Network
- Dynamic, proactive and automatic configuration of Server, Storage and Network
- Same people to do Server, Storage and Network

Some vendors will put emphasis on different elements of the above points. A key point to note is that Converged Infrastructure (IMHO) is more than just physical it is also the management tools (which leads as a consequence to convergence of I.T. organisation processes)

From a physical view it might look like this - compare this with our picture above.



Note: This is a picture of a Cisco UCS Blade Chassis - 6U in size, so that is 7 chassis (at a push) in a 42 rack, each chassis has max 8 cables (normally 4) so the total number of cables is 56 cables (doesn't sound much better). However there would be 56 servers in the rack (slightly more than 8 in previous example) and single pane of management to go with it - more about Cisco UCS in another post.

Next posts - FCoE, Data Center 2.0/3.0 and Data Challenges