Thursday, September 29, 2011

Cisco UCS-C Servers Rack Mounting Adapter Kit

The Cisco UCS-C Series servers come with a terrific tool-less slide rail kit. The rail kit is compatible with 3/8" square hole and 1/4" round hole racks. The rail kit does not work with 2post racks and threaded hole racks.

I found two adapter kits from The Server Rack.

The Threaded Hole Rack Adapter Kit

The 2Post Rack Adapter Kit

That is all...


Monday, September 26, 2011

VMware ESXi 4.1 Optimizations for Cisco UC on UCS

In my previous post I discussed the importance of installing the latest version of VMware Tools on UC virtual servers in a Cisco UC on UCS deployment. A second and equally important VMware 'tweak' is disabling Large Receive Offload (LRO) on VMware ESXi hosts.

VMware Knowledge Base Article 1027511 addresses some Linux TCP/IP stacks perform poorly when handling LRO-generated packets. This results in poor TCP performance.

    Cisco UCS Servers at VMworld
  1. Log into the ESXi host or its vCenter with vSphere Client.
  2. Select the host > Configuration > Software:Advanced Settings.
  3. Select Net and scroll down slightly more than half way.
  4. Set the following parameters from 1 to 0:
    1. Net.VmxnetSwLROSL
    2. Net.Vmxnet3SwLRO
    3. Net.Vmxnet3HwLRO
    4. Net.Vmxnet2SwLRO
    5. Net.Vmxnet2HwLRO
  5. Reboot the ESXi host to activate these changes.

Your guest VMs should now have normal TCP networking performance.

VMware Knowledge Base - KB Article 1027511
Cisco UC on UCS - Don't Forget VMware Tools


Monday, September 19, 2011

Cisco UC on UCS - Don't Forget VMware Tools

Recently we upgraded a Cisco Unified Communications system running on physical HP servers, to Cisco UCS C-Series rack mount servers. Three days after the upgrade, all of the UC applications slowed down.

When users picked up their phone handset, there was a noticeable delay before dial tone. Delayed dial tone is a classic symptom of an overworked CallManager.

The Cisco UCS C210M2 servers were more than adequate for the load. Each UCS-C210M2 hosted VMware VMs of CallManager, Unity Connection, and UCCX. All of the VMs were deployed using the Cisco prescribed OVA templates.

Cisco UCS-C210M2
Cisco UCS C210M2

So what is “VMware Tools”?

According to

VMware Tools are specialized drivers for virtual hardware that is installed in the UC applications when they are running virtualized.

Now I understand Drivers. Up to date drivers are a good thing. Docwiki goes on to state:

It is very important that the VMware tools version running in the UC application be in sync with the version of ESXi being used.

Anyone who has read Cisco documentation before should realize, Cisco doesn’t often use the phrase “it is very important”. This is as close as Cisco gets to saying “you have to do this”.
So we installed VMware tools on all of the VMs and the Cisco voice system has been stable ever since.

Cisco has 3 methods for installing VMware Tools on Unified Communications Application VMs dependent on the UC Application version. Visit DocWiki-VMware Tools to find the appropriate method.

Please Note: VMware Tools will have to be re-installed anytime VMware ESXi is patched or upgraded.


Tuesday, September 13, 2011

Touchpad Lack of Apps? I don't need no stinking apps

I have had my Touchpad for about 4 weeks. It have spent most of this time tweaking and reading books with the Kindle App. For the last year I have been debating whether to get an iPad or Android tablet or an eReader such as a Kindle or Nook.

I have an iPhone which I really like. I like the vast array of applications. My favorite and most used iPhone apps are Echofon (twitter), Google+, Evernote, SkyGrid, AP Mobile, CNBC, YouTube,, Zynga Poker, Yelp, Dropbox, USA Today, YouVersion Bible, and Amazon Kindle.

I primarily use my iPhone for, besides talking and texting, to keeping up with Twitter and Google+, news and stock information, reading books work related PDFs. I really enjoy the iPhone Kindle app. In the last year I have read about 10 books.  The screen is small and I just get into a rhythm of turning the page every 5 seconds.

So I wanted a tablet type device specifically for reading. Being stubborn and difficult, I didn't want to forego the opportunity to surf the web. In short I wanted an eInk  reader that could switch to an iPad. Well that device doesn't exist, so I kept reading on my iPhone.

Then we got a call in the office. Our company had purchased a quantity of HP Touchpads. These were made available for sale, one per employee. I did a Google search and saw the Kindle was available on the Touchpad. So I bought one.

After 4 weeks I can say I am love the Touchpad as an eReader, and I am adjusting to the new mindset of the WebOS. I love the Kindle app (enough about that). I keep thinking the WebOS is hindered by the lack of apps.

However, WebOS supports Flash. This causes a bit of a change in mind set. Many iPhone/iPad apps exist because a webpage running a Flash app isn't possible. So if a web site I frequent uses Flash, WebOS supports Flash, the Touchpad doesn't have an app for the site, and I can just go to the website and do what I want, do I care there isn't an app?

Here is a more concrete example....Sunday I was watching the NFL games and wanted to track my Yahoo Fantasy Football team. My iPhone doesn't support the flash based "stattracker" realtime interface. The iPhone Yahoo Fantasy Football app will show updated stats in a vanilla interface that reloads every minute.  Basically the app is the same experience was the iPhone web page but with automatic reloads.

I pulled out the HP Touchpad, went to the web site, and launched the flash based stattracker and followed the beautiful realtime stats. Wow! The web page was great, no special app needed.


Sunday, September 11, 2011

9/11 - My Day

9/11/2001 Started out as a normal day for me. I remember it was a beautiful day. Mid 70s and not a cloud in the sky. If things at work went well I was going to sneak out early.

I was at a customers integrating a firewall with a web content filter. I had the basics working and moved on to the more advanced parts. One of the customer's employees came into the room and announced two planes had crashed into the World Trade Center. She found a TV and moved it into the conference room.

I hurried to get my work done so I could get to watching TV. I felt numb. I remembered the previous attack on the WTC. I had assumed that was an isolated incident by a few radicalized, American hating, muslims whom learned how to build a "fertilizer" bomb from the Internet.

My phone rang a couple of times. It was my wife. I was thankful she called. We shared in our shock at what was happening and exchanged "I Love You's".

Then my phone rang again. I didn't recognize the number other than it was a downtown Chicago number. I answered the phone to hear an obviously crying female voice say hello. I recognized the voice as a customer.

The last couple of months I was doing some work for her company. Her office was in an unique location. Her office, and the computer systems she supported, was located within the Federal Reserve Bank of Chicago.

The Federal Reserve Bank of Chicago is a few blocks of the former Sears Tower.

Hearing her sobs I said, "Hello. Are you ok? What can I do for you?".

What she said stunned me....

Struggling to compose herself she said, "Two plans flew into the World Trade Center. We were just told a plane is flying towards the Sears Tower. The building is being evacuated. My boss told everyone to get out."

The gentle sobs erupted into a flood of fear, panic, and terror. "My boss told everyone to get out except me... I have to stay and watch our systems to make sure they are secure." "He said if someone else will watch the systems, I can leave!!"

"Go!!" I said. "Thank you" is all I heard.

I talked to her a couple of times in the next two or three days, but never after that. For the next week I monitored their systems and saw nothing unusual.

I was happy to learn she left her employer a few weeks later.