Quick ESXi 6.5 review

I had intention to install ESXi 6.5 on spare disk of my old PC. ESXi 5.1 worked quite well there.

I like these features of ESXi (when compared to other hypervisors):

• very comfortable C# VI Client (unfortunately until 6.5 ESXi only, but I don't care because it is last edition that also supports my hardware).
• real memory overcommit - ESXi allows VMs to allocate more memory than the free memory on ESXi server. It uses ballooning and VM swapping to overcome memory exhaustion problem.
• reliable pause function - ESXi is able to reliably pause and resume VMs (this works much better than suspend on most notebooks - whether is it just coin flip chance if the notebook will really resume or just lockup). It is very handy when you need to reboot server and reduce VMs downtime to shortest possible time on single server.
• virtual disks can be shared among VMs even when underlying storage is old SATA disk (which does not support sharing at all). This feature is handy when testing software that requires shared storage (for example Oracle RAC - I tested this even on ESXi 3.5 years ago - last version ESXi that worked on 32-bit CPUs)
• easy creation and managmenet of virtual switches - again it can be used to test misc cluster software (which often requires dedicated Heart-Beat network)

NOTE:

Although I mentioned cluster several times I don't recommend clusters for production. In my experience cluster very often reduces availability because of complexity and fragility (proper cluster behavior strongly depends on many timeout settings and proper fencing which is often nearly impossible to achieve).

However - my AMD X2 CPU is no longer supported by ESXi 6.5 (it's fatal installation error).

You can read more about this for example on https://www.reddit.com/r/vmware/comments/5ec5vl/esxi_65_the_cpu_in_this_host_is_not_supported_by/

Fortunately I can still use ESXi 6.0 (including 6.0 Update 3A, releae date 2017-07-11, Build# 5572656). I just got warning about unsupported CPU and about missing Hardware virtualization (meaning lack of IOMMU virtualization support - I can live quite well without it), but it still works well.

My test PC is:

• CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 3800+
• MB: MS-7250
• 6GB RAM
• 200GB SATA Maxtor disk

And it seems to work quite well (the only encountered HW problem was NVidia chipset overheating - I just laid down Fan for Power supply and it is now rock stable).

Tips

Disabling gfx mode switch

CentOS 6 guests attempt to switch text mode to ridiculous resolution where letters are in "dwarf mode". To disable this mode switch add following to kernel parameters in grub:

nomodeset nomodeset.vmwgfx=0

This (modified) tip comes from: https://wiki.archlinux.org/index.php/kernel_mode_setting#Disabling_modesetting

Installing Win2008R2 on PV disk

To Install Windows 2008 R2 on Para Virtualized PV SCSSI disk do the following in "Create New Virtual Machine" Wizard:

• select Custom Type configuration
• I used "Virtual Machine Version: 8" (compatible from ESXi 5.0 upwards)
• select "VMXNET 3" network card for best performance
• select VMware Paravirtual for "SCSI controller"

After VM creation do following:

• attach your install ISO (7601.17514.101119-1850_x64fre_server_eval_en-us-GRMSXEVAL_EN_DVD.iso in my case) to 1st DVD drive
• add 2nd CD/DVD driver - ensure it is assigned to IDE controller after install ISO
• attach /vmimages/tools-isoimages/windows.iso to it (this path works at least for ESXi 6.0)
• boot your VM
• when asked for Driver disk, click Browse and select E:\Program Files\VMware\VMware Tools\Drivers\amd64
• you should now see target disk and you can continue installation as usual
• after Win installation do not forget to install VMware guest tools (you can use already mounted E: drive) and to install network driver