UCS - False duplicate IP address detected on Microsoft Windows Vista and later virtual machines on ESX/ESXi when using Cisco devices on the environment

Symptoms

• When you assign an IP address on Windows Vista and later versions, you see a duplicate IP address conflict.
• When you restart Windows Vista and later versions, you receive a 169.254.x.x IP.
• When you set up the same virtual machine on a vSwitch with no uplink port on the vSwitch, the IP address is assigned successfully.
• When you assign the same IP address to a Windows 2003 virtual machine on the same vSwitch, the IP address is assigned successfully.

Cause

This issue occurs when the Cisco switch has gratuitous ARPs enabled or the ArpProxySvc replied to all ARP requests incorrectly.

Resolution

Note: The information provided in this article is a workaround. Investigate the network configuration at the physical layer for the root cause. For more information regarding this topic from Cisco please see Duplicate IP Address 0.0.0.0 Error Message Troubleshoot

To work around this issue, turn off gratuitous ARP in the guest operating system.

Note: This procedure modifies the Windows registry. Before making any registry modifications, ensure that you have a current and valid backup of the registry and the virtual machine. For more information on backing up and restoring the registry, see the Microsoft article 136393.

Note: The preceding link was correct as of April 24, 2014. If you find the link is broken, provide feedback and a VMware employee will update the link. 

To turn off gratuitous ARP in the guest operating system:

1. Shut down the guest operating system and power off the virtual machine.
2. Change the virtual machine to a network vSwitch with no uplink. You can create one for this procedure.
3. Power on the virtual machine and log in.
4. Open the Registry editor.
   
   • In Windows XP to Windows Server 2003 - Click Start > Run, type regedit, and click OK.
   • In Windows 7 and Current - Click Start, type regedit, and click OK.
5. Locate this registry key:
   
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
6. Click Edit > New, and click DWORD Value.
7. Type ArpRetryCount.
8. Right-click the ArpRetryCount registry entry and click Modify.
9. In the Value box, type 0 and click OK.
10. Exit the Registry Editor.
11. Shut down the guest operating system and power off the virtual machine.
12. Change the virtual machine back to a network vSwitch with the uplink.
13. Power on the virtual machine.

Alternatively, you can disable gratuitous ARP on the physical switch.

For example:

To disable gratuitous ARP in Cisco IOS, run this command:


# no ip gratuitous-arpshttp://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1028373

vCPU configuration. Performance impact between virtual sockets and virtual cores?

vCPU configuration. Performance impact between virtual sockets and virtual cores?

Best Practices for Performance Tuning of Latency-Sensitive Workloads in vSphere VMs

PDF Link

UtilityUNetbootin ISO to USB

UNetbootin allows you to create bootable Live USB drives for Ubuntu, Fedora, and other Linux distributions without burning a CD. It runs on Windows, Linux, and Mac OS X. You can either let UNetbootin download one of the many distributions supported out-of-the-box for you, or supply your own Linux .iso file if you've already downloaded one or your preferred distribution isn't on the list.

Determination, Dedication, Persistence, and prayer.... VMware VCAP-DCA Exam acquired!

..what I had to study to pass the VCAP-DCA + hands on

   

Advanced vSphere 5.x Storage – Masking, Multipathing & Filtering

The relationship between a vSphere ESXi host and its shared storage is very important for the solution to work effectively. The storage architecture within vSphere is extensible and this extensibility is known as the Pluggable Storage Architecture often abbreviated to PSA.

The PSA is an open modular framework that coordinates the simultaneous operation of multiple multi pathing plugins (MPPs). PSA is a collection of VMkernel APIs that allow third party hardware vendors to insert code directly into the ESX storage I/O path. This allows 3rd party software developers to design their own load balancing techniques and failover mechanisms for particular storage array. The PSA coordinates the operation of the NMP and any additional 3rd party MPP.

VCAP-DCA: esxcli Command List for Storage

In studying for the VCAP-DCA5 I have been using several great resources, Jason Nash’s VMware vSphere Optimize and Scale class @ Pluralsight, the #vbrownbag videos on You Tube, and The Unofficial VCAP-DCA5 Study Guide by Jason Langer and Josh Coen. One thing that I have learned is that I really need to study the esxcli command namespace and know when and how to use it.

To that end I have complied a concise list of all the commands from Langer and Coen’s guide in one place so I can quickly reference them as practice in my lab. This is not meant to teach or explain the commands, their guide does a great job of that already. The goal here was to create quick study sheet for lab use.

Because of the size of the Blueprint I have broken the list down by section. The following list contains all the esxcli commands that one needs to know for Section One: Implement and Manage Storage.

Disable automatic host registration
esxcli system settings advanced set -i=0 -o “/Disk/EnableNaviReg”

Increase Max NFS volumes
esxcli system settings advanced set -i=32 -o “/NFS/MaxVolumes”

Increase the TCP Heap Size
esxcli system settings advanced set -i=16 -o “/Net/TcpipHeapSize”

Adding a LUN with an Existing VMFS Volume
esxcli storage vmfs snapshot list
esxcli storage vmfs snapshot mount -l ‘replicated_lun’
esxcli storage vmfs snapshot resignature -l ‘replicated_lun’

Understand and apply LUN masking using PSA-related commands
esxcfg-scsidevs -m — the -m
esxcfg-mpath -L | grep naa.5000144fd4b74168
esxcli storage core claimrule add -r 500 -t location -A vmhba35 -C 0 -T 1 -L 0 -P MASK_PATH
esxcli storage core claimrule load
esxcli storage core claiming reclaim -d naa.5000144fd4b74168

Unmask a LUN
esxcli storage core claimrule remove -r 500
esxcli storage core claimrule load
esxcli storage core claiming unclaim -t location -A vmhba35 -C 0 -T 1 -L 0
esxcli storage core adapter rescan -A vmhba35

Identify and tag SSD devices
esxcli storage core device list
esxcli storage nmp device list
esxcli storage nmp satp rule add -s VMW_SATP_DEFAULT_AA -d naa.5000144f60f4627a -o enable_ssd
esxcli storage core claiming unclaim -t device -d naa.5000144f60f4627a
esxcli storage core claimrule load
esxcli storage core claimrule run

Display Hardware Acceleration Plug-Ins and Filter
esxcli storage core plugin list -N VAAI — displays plugins for VAAI
esxcli storage core plugin list -N Filter – displays VAAI filter

Displaying whether the device supports VAAI and any attached filters
esxcli storage core device list -d naa.6006016014422a00683427125a61e011

Display VAAI status of each primitive on a device
esxcli storage core device vaai status get -d naa.6006016014422a00683427125a61e011

Display the current claim rules for filters and for VAAI
Filter — esxcli storage core claimrule list –c Filter
VAAI – esxcli storage core claimrule list –c VAAI
esxcli storage core claimrule add -c Filter -P VAAI_FILTER -t vendor -V vlabs -u
esxcli storage core claimrule add -c VAAI -P VMW_VAAI_VLABS -t vendor -V vlabs -u -f
esxcli storage core claimrule load -c Filter
esxcli storage core claimrule load -c VAAI
esxcli storage core claimrule run -c Filter

Unmount a Datastore
esxcli storage filesystem unmount -l vmfs_vcap_masking

Mount a Datastore
esxcli storage filesystem mount -l vmfs_vcap_masking

Upgrade VMFS3 to VMFS5
esxcli storage vmfs upgrade -l vmfs3_upgrade

Check to see if a new plug-in is registered
esxcli storage core plugin registration list

Register a plugin
esxcli storage core plugin registration add -m vcap_satp_va -N SATP -P VCAP_SATP_VA

Set a new default PSP for a SATP
esxcli storage nmp satp list
esxcli storage nmp satp set -s VMW_SATP_CX -P VMW_PSP_RR
esxcli storage nmp satp rule add -s VMW_SATP_CX -d naa.5000144f60f4627a
esxcli storage nmp satp rule list -s VMW_SATP_CX

Changing the PSP on a particular device
esxcli storage nmp device list -d naa.5000144fd4b74168
esxcli storage nmp device set -d naa.5000144fd4b74168 -P VMW_PSP_FIXED

View the device configurations for devices assigned the RR and Fixed PSPs and the generic
esxcli storage nmp psp fixed deviceconfig get -d naa.5000144ff548121b
esxcli storage nmp psp generic deviceconfig get -d naa.5000144fd4b74168
esxcli storage nmp psp roundrobin deviceconfig get -d naa.5000144fd4b74168

Set the preferred path on a device using VMW_PSP_FIXED and customize different parameters for a device using VMW_PSP_RR
esxcli storage nmp psp fixed deviceconfig set -d naa.5000144ff548121b -p vmhba35:C1:T0:L0
esxcli storage nmp psp fixed deviceconfig get -d naa.5000144ff548121b
esxcli storage nmp psp roundrobin deviceconfig set -d naa.5000144fd4b74168 -I 2500 -t iops
esxcli storage nmp psp roundrobin deviceconfig get -d naa.5000144fd4b74168

Set the device back to the VMW_PSP_RR default
esxcli storage nmp psp roundrobin deviceconfig set -d naa.5000144fd4b74168 -t default

Changing a device that is using the VMW_PSP_RR plug-in
esxcli storage nmp psp generic deviceconfig get -d naa.5000144fd4b74168
esxcli storage nmp psp generic deviceconfig set -d naa.5000144fd4b74168 -c ‘iops=5000′

iSCSI port binding
esxcli iscsi networkportal add -A vmhba35 -n vmk1
esxcli iscsi networkportal list

By Byron Schaller |