Host Becomes disconnected

In my current role I have inherited a largish vSphere 4.1 environment, that has to put it nicely “evolved”.  We have been having host disconnection issues in one of the clusters, coupled with HA Configuration errors.  well today one host disconnected and absolutely refused to reconnect, bizarrely it kept telling us that the username/password combination was incorrect within vCenter.

So we jumped on the ILo and entered the SAME username and combination and low and behold we gained access to the promised land.  Now I know what you are thinking “CapLocks”, but no checked that.

My next troubleshooting step was to restart the management agents on the errant host but again this did not fix the error.

The I had a “lightbulb” moment, as we checked the network settings on the host. I saw that the gateway address was incorrect, it was configured with a correct gateway address but for the wrong subnet.  it was set to the vMotion network not the Management network. reset that and all of a sudden we could rejoin vCenter.

I then checked the rest of the Hosts in the Cluster and found the same basic configuration error, we reset the gateway across the cluster and low and behold now HA works as designed and no more configuration errors.

Moral of this story is “Check the Basics”

Things from VMware you really should subscribe too.

VMware are possibly on of the best companies out there on managing So-Me (social media), the amount of information that they provide can be baffling at times, especially now that they have such an impressive array of products. however they do provide a set of very useful email and RSS Feeds, the one that I personally find most useful is the Weekly updated KB, well how else can you keep unto date with so many products.

As I have already said I get a weekly digest in my email every week.  So how can you get this in your email box weekly. Easy just follow these few simple steps.

Navigate to and click the subscribe link.

Vmware site

you will be forward to another page were you can chose your delivery options

KB Digest

And that is how I keep up to date on the Knowledge Base Articles.

Virtualisation 101 – VMware Update Manager (VUM)

What Is It?

Update Manager is VMware’s patching product, and is used for updating ESX/ESXi hosts, virtual appliances and guest machines.  It is a companion product to vCenter and installed via the vCenter Installer.  In smaller deployments VUM would be installed on the vCenter server, but in larger environments could be run as a dedicated server.

The application can run scheduled download of patches from VMware and Shavlik (for Microsoft updates) and store them in a local repository.   Patches can also be imported from ZIP files, or via an intermediary machine running Update Manager Download Service (UMDS).

Management of VUM is done via a vSphere Client plugin, which adds an extra icon in the Solutions section, and an Update Manager tab to each vSphere object.   Patching is done in 3 steps :-

  1. 1.       Baselinesare created to set the types of patches to apply, which are then attached to objects within the hierarchy: datacentre, cluster, resource pool, folder, vApp or an individual host or guest.  Multiple baselines can also be aggregated into a baseline groups.
  2. 2.       A scanof the attached object compares the ESX/ESXi hosts, Windows or RedHat Linux guests against the baseline profile to report which are compliant or which have patches that need to be applied. 
  3. 3.       Finally you remediatethe ESX/ESXi host or Windows guests to apply missing patches.  VUM automatically places hosts into Maintenance Mode (providing DRS is set to Automatic) before patching begins to avoid any outages, and can apply snapshots to virtual machines before patching, retaining them for a predetermined period of time afterwards, providing a handy rollback option.

VUM installs a Guest Agent on Windows or RedHat virtual machines at the first scan or remediation to facilitate patching.   Please note that — as of v4.1 — VUM cannot scan non-RedHat distributions of Linux, nor can it remediate any Linux guests with OS patches, only applying updates for VM Hardware and VMTools.  

Windows guests from XP or above can have OS patches installed — even up to full Service Packs — while online or offline.  VUM can also upgrade their VM Hardware level and VMTools.

What Do I Need to Deploy It?

The good news is that you don’t need a great deal to deploy the latest version of VUM :-

  • A 64-bit virtual or physical Windows server(XP, 2003 or 2008) with at least 2Gb of RAM (if dedicated to VUM) – if running alongside vCenter you’ll want at least 4Gb of RAM.
  • A databasefor holding the application metadata – this could be a local SQL 2005 Express database for smaller implementations (bundled with it), or a local or remote MS SQL Server 2005/2008 or Oracle 10g/11g.   The database size can be determined with the Update Manager Sizing Estimator (see link below).
  • Disk space for the patch repository.  The amount of space required will vary depending on what is to be patched.  Again the sizing estimator can gauge disk space requirements, but as an indication the install will warn if less than 20Gb is free on the chosen volume.
  • Network connectivityand firewall access for the application to communicate properly with the vCenter server, database server, ESX/ESXi hosts and the Internet.  For full details of ports used see KB article 1004543 (link below).

Should I Use VUM Instead Of Microsoft WSUS?

In theory VUM’s patching technology is sound – Shavlik has been around since 1993 – and does the job well.  However, many companies choose to stick with WSUS as the infrastructure is already in place and works, or because Windows admins feel safer staying “in-house”.  

OS patching aside, VUM is still useful for upgrading VM Hardware and VMTools on Windows guests.

How Much Does It Cost?

VUM is covered by any level of vSphere licensing, so the only implementation costs apart from time and effort are potentially OS or database licenses. 

Where Do I Go From Here?

VUM Documentation Page:

The official Install & Admin Guide:

VUM Sizing Estimator:…/doc/vsp_vum_40_sizing_estimator.xls

Network Ports Required:

Video of VUM in action:

Warning ESX U2 and PCoIP

VMware have been touting all over twitter today about an issue but not actually informing us what it was, there have been rather cryptic warning about about a Issue with ESX U2 and VDI,  now these warning have been going out since early morning UK time and it is now 8pm UK time and finally:

Continue reading “Warning ESX U2 and PCoIP”