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KB84417 Storage vMotion fails at 78% and freezes VM Operation for a longer time

Some weeks ago we hit an issue whereas storage vMotion failed and operation rollback caused 10 to 15 minutes freeze of the affected VM. It turned out that this only happend to bigger VMs meaning more then 300GB RAM configured. There is finally a KB available by VMware but the workaround they provide needs you to shutdown the affected VM. This was not an option to me so i decided to go the PowerCLI way!   Storage vMotion fails at 78% when migrating VMs accompanied by intermittent VM crashes (84417) (vmware.com) $vm = get-vm VMName New-AdvancedSetting -Entity $vm -Name sched.mem.pshare.enable -Value false This will disable the pSharing Feature. After setting this, you have to vMotion the VM to a new host, that will recreate the world and reload the vmx thus enabling the new setting. After this I was again able to do storage vMotion and everything beeing kept online. Hope this helps.

Bad Performance for VM on AMD Gen2 EPYC

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 As we recently deployed some new second Gen AMD EPYC Servers ProLiant DL325Gen10 Plus using AMD EPYC 7542 we saw some very strange CPU performance problems. Meaning a 1:1 mapping from physical to virtual CPUs was showing very high ready times up to 30%. There were some fixes in the scheduler in 7.0.2 but still the problem persisted. There is a very good tuning guide  https://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/techpaper/performance/vsphere70u2-cpu-sched-amd-epyc.pdf that helped me to find the issue. Problem seems to be that the default setting in the HPE Bios for Numa memory domains per socket (NPS) is set to Auto that doesn't seem to work well with ESXi. When setting this to NPS-1 performance is as expected and no ready times seen. Hope HPE will explain more on the "Auto" setting.

Brocade FOS Dynamic Portnames

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 As i´m playing around with new Brocade SAN Switches i wanted to clean up a little bit and one thing that i found very useful are dynamic portnames. This feature will change the portname of the switchport according to the connected device. To enable it run `configure` and enable Dynamic Portnames, this can be done online: You then can change the behaviour on how the ports will be named by changing the "formatstring" or live with the default <switch name>.<port type>.<port index>.<alias name> With FOS 8 you can change this now and select the following parameter e.g.  portname -d "S.T.I.F.A.R" you will get the explanation by running "portname -d -help"

VMware Tanzu, when configuring Workload Network portgroup, no portgroup is shown

 Just recently i had an issue where i wanted to configure Workload management to test Tanzu I had trouble finding the intended portgroup. It turned out that my vDS was inside a network folder in the vCenter inventory. After moving it out of the folder, i was able to see the portgroups. Hope i could solve this for some of you strunggling ;)  cheers!

PC takes ages to boot and how to look at it

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 Just recently i had multiple VMs that took about 20 minutes to boot. There is a very neat tool to analyse the Windows Boot process called xbootmgr Using "xbootmgr -trace boot" I was able to see that "autochk" was taking most time of the boot process.  Googling around lead to the point that autochk thinks that the disk is dirty, may do a checkdisk but doesn´r remove the dirty flag. Solution for me was manually adding that dirty flag to the partition and reboot, causing autochk do fully run a check and finally it cleand up the state. Setting the state is done by calling "fsutil dirty set C:" and if you have multiple partitions you may change the drive letter here. Hope it helps!

iLO LDAP configuration for ActiveDirectory integrated login

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 As I was struggling a long time to get this done right and finally have a solution now I feel that it is a good thing to share with you. Using LDAP Authentication in iLO enables you to just use your domain credentials instead of endless lists of random passwords. For AD there is a neat thing and some caveats to consider that caused outages to the iLO login page when done wrong. The only things you have to fill in here is  - Directory Server Address - Directory User Context 1 (do not fill in DC=domain,DC=corp) but @domain.corp  - desired LDAP Port (636 by default) - Use Directory Default Schema Hope it´s helpful to you.

vCenter update stuck "Data conversion/Post install hook failed" and how I fixed it

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 I was updating a vCenter instance from 7.0 to 7.0.1a but got this error message but everything else seems to work fine.  I just cleared the install state using this procedure  and was able to use VAMI again. Oddly after clearing the update status VAMI was showing the old build number whereas the vSphere Client shows the new one.  After some days there was 7.0.1b released and I tried this again but was stuck again at that point. Just yesterday I tried it again with 7.0.1c but the "Stage" and "Stage and Install" buttons were grayed out. So I digged a little and prepared the VCSA, after that the buttons got clickable again: Backup your appliance first! root@vcsa [ /storage/core/software-update ]# mv install_operation install_operation.bak root@vcsa [ /storage/core/software-update ]# mv stage_install_operation stage_install_operation.bak root@vcsa [ /storage/core/software-update ]# mv stage_operation stage_operation.bak root@vcsa [ /storage/core/software-update/updates