Friday, September 21, 2012

Lose your ssh key pub file?

I somehow lost my ssh key pub file, which is inconvenient when I want to copy it out to other hosts.  I could grab it from another host's authorized_key file, but wouldn't it be easier just to recreate it?  Here's how to do it.

[reamer77@myhost .ssh]$ ssh-keygen -y > id_rsa.pub
Enter file in which the key is (/home/reamer77/.ssh/id_rsa):
Enter passphrase:


Viola.  You should now have your pub file back without having to generate a new private and pub key file.

Tuesday, August 28, 2012

VMworld 2012 - Day 1 Notes

 Keynote

 I won't go into too much detail.  You can see it for yourself at http://vmware.com/go/keynote. You can suffer through the dialogue in the beginning, or fast-forward to the actual start at around 5:18.

What you won't see is the insane performance before Paul Maritz came on stage.  The hall was packed when I showed up just in a nick of time.  A drum line came out and played on drum pads that spelled out VMworld 2012.  Then there was some beat boxing, singing and dancing.  Pretty nuts.  Pretty loud.  And I thought with the tag line "Right Here, Right Now" we'd have Jesus Jones or Van Halen.

During the reviews of the talks and events, I saw there is a speaker from Virginia Tech on Thursday (Dr. Dennis Hong, Director for Robotics and Mechanisms Lab). Go Hokies! I was disappointed to see they referenced him as from "Virginia Tech University".  When did my school become VTU?  It's VPISU (Virginia Polytechnic Institute and State University) from what I remember.

Maritz talked about where VMware is going, and about trying to find out how to give users new experiences in receiving information in real time.  Of course, the talk about integration and automation, and supporting multiple mobile devices.

And then I found out there's going to be a new sheriff in town.  May have not been news to anyone else, but I don't follow VMware's operations that closely.  A cartoonish screen shows a stage cane yanking Maritz off the screen and a big picture of the soon-to-be new CEO, Pat Gelsinger.  Gelsinger's delivery seems totally opposite from Maritz in his delivery.  In comparison, he sort of reminds me of that scene in Trainspotting with Spud's job interview (I'm grossly eexaggerating, but it's pretty polar).  I wonder how this will play out with VMware: an energetic head of the company.  It could bring life and energy, or will they lose focus with all of that energy?  Gelsinger's phrase was "Abstract.  Pool.  Automate."  He also talked about yearly releases of vSphere.  I wonder how that will change the product's lifecycle and support.

Then the CTO, Steve Herrod, was up.  His presentations seemed pretty rushed.  I'm guessing so he could fit in what he wanted to talk about.  vCloud Director seemed interesting, but I couldn't really follow from where I was sitting near the back of the room and right.  I didn't really understand the Serengeti/Hadoop presentation either..  I'll have to look into vCenter Operations Manager when I get back to the East Coast.

Architecting a Cloud Infrastructure

You may find something interesting from others that attended by searching Twitter and #VSP1168

This was a pretty good session.  No real dirty technical details, but really showed you how to give thought to developing your cloud infrastructure.  A lot are "common sense", but sometimes forgotten.  Some of my key takeaways were

  • Get good requirements from your customer or your business
  • Don't necessarily assume published "Best Practices" apply to you.  Read the Best Practices and determine for yourself.  For instance, some Best Practices developed during vSphere 4.x don't apply any longer, since some constraints were lifted in vSphere 5.x.  So, basically, use them as a guide, but not heavily depended on.
  • Add conceptual diagrams to your architecture diagrams.  Treat your architecture diagrams as a story book.
  • For sizing and scaling, VMware Capacity Planner is a really good tool.
  • For compute considerations, memory is generally your bottleneck, but don't assume that.  Know your apps.  The panel suggest the sweet spot for hardware is 96GB RAM with 2 sockets.
  • Networks are generally not the bottleneck.  10GbE networks should be adequate for growth.
  • In the discussion of booting ESXi servers, the panel said that the "best of all worlds" solution was PXE Boot, and to investigate GUI Fling.

Update Management for Physical and  Virtual Machines

OPS-CIM2661

I came into this one looking for tips on managing my OS's.  Come to find out, this was all about a VMware product called vCenter Protect.  For the foreseeable future, it only handles updating of Windows hosts, and nothing on the roadmap to support Linux or Mac.  I ended up leaving, since this isn't in my realm of operations, and the Windows guys use other products such as Altiris.

Avoiding the 19 Biggest HA & DRS Configuration Mistakes

You may find more information by searching Twitter hash tag, #VSP1232

This was presented by Greg Shields.  I've never been to one of his presentations, but I really found him entertaining.  Here's the high level 19.

1.  Not having similar processors in cluster for vMotion (whether at time of implementation or hardware refresh)
2.  Not planning for svMotion
3.  Not enough cluster hosts to support failover (use Admission Control Policy)
4.  Setting host failures the cluster tolerates to 1
5.  Forget to prioritize VM restarts (policy is defined per host, not globally)
6.  Disabling notifications from "Admission Control Policy" (see #3)
7.  Not updating percentage policy (the preferred method of setting failover resources)
8.  Buying the occasional big server (host failures must set aside outsources of the largest server)
9.  Neglecting Host Isolation Response
10.  Assuming that datastore heartbeat in vSphere 5.x will prevent isolation events
11.  Confusing "All Points Down (APD)" with "Permanent Device Lost (PDL)"
12.  Overdoing reservations, limits, and affinities
13.  Considering using shares without using shares
14.  Doing memory limits on VM's (DON'T DO IT)
15.  Thinking you're smarter than DRS
16.  Not understanding DRS equations
17.  Being too liberal (with DRS migration thresholds)
18.  Having VDI and server workloads in the same cluster
19.  Planning on overcommit (assign the right memory and CPU values to your VM's)

Become a Rock Star with Power CLI and vCenter Orchestrator

More information may be found by searching Twitter hash tag #VSP1856

This was presented by Josh Atwell (@josh_atwell), and was another entertaining talk.  It was pretty high level and didn't get into nitty-gritty scripting, but it was pretty informative for someone like me who never gave Power CLI much thought.

Some of my key takeaways (again some are Common Sense that you don't necessarily think of).
  • If you have common tasks that you do over and over again, try to automate it.  
  • Biggest strengths of Power CLI are data gathering, and bulk configuration changes to VM's
  • Planning of Automation - "Where are you now?  Where do you want to be?"
  • Check out Project Onyx.  It's a proxy to vSphere and will record the actual commands being executed within the GUI.  It will then output these to commands that can be run by Power CLI and vCenter Orchestrator
  • How to be a Rock Star?  Practice!  And finding items and implementing them.
  • "Today's miracles are tomorrow's expectations." Especially when you bust your hump to deliver miracles to the business or customer.
  • If you need help on something, post to Twitter with the appropriate hash tags.  People will generally respond.

Other notes

I finally got in to do a Hands On Labs (hasn't been less than a 60 minute wait these past two days to get in).  I did the vCloud Director lab.  It seemed pretty cool.

I missed out on #vFlipCup.  I'm disappointed.

Monday, August 27, 2012

VMworld 2012 - Day 0

Notes for Day 0 at San Francisco / VMworld


Here are my notes of my first full day in San Francisco. I call it Day 0 since none of the official talks have occurred yet. I will try to post my daily notes and experiences from SF/VMworld on this blog for the next few days, as time and other mitigating circumstances permit.

Walking

  • The hills in SF are no joke. We walked to the Wharf. I should've ditched my compadres and taken a bus or street car instead of walking back to the hotel.
  •  Chinatown is HUGE, and they like grocery shopping on Sunday.  It was tough walking up Stockton with all the produce shopping on the sidewalk.

Wharf 

  • Alcatraz doesn't look *that* far. Determined people couldn't swim that?
  • I didn't find the Bushman, but I wasn't looking either
  •  The pedestrian bridge crossing the street to Pier 39 is a good place to stop and look around and see the sights from a high, non-crowded vantage point
  •  After wondering why I was seeing helicopters hover around the Golden Gate Bridge for a while, I realize there's a big boat race going on. Come to find out later, it was an America's Cup race. You win again, Larry Ellison (damn you).

VMworld 

  •  This conference is a lot bigger than I thought it would be. It's in 3 buildings, and the fourth building has all the vendors
  •  The vendors really make you work for "free" tshirts now. You have to have your attendee badge scanned, sit through presentations, and tweet their company names. I was starting to think I was going on a free trip at a time-share
  •  Billy Mays would've been an awesome presenter for some of these products at the Vendor Booths
  •  I guess the usage of "Booth Babes" is dead now. Where did they go? 

I will try to post Day 1 notes tomorrow.  I'm signed up from 8:30am to 6pm.  It's gonna be a long day.