ESXTOP - Deep Dive

Source - www.yellow-bricks.com

ESXTOP

Intro
Thresholds
Howto – Run
Howto – Capture
Howto – Analyze
Howto – Limit esxtop to specific VMs
References
Changelog
This page is solely dedicated to one of the best tools in the world for ESX; esxtop.

Intro

I am a huge fan of esxtop! I read a couple of pages of the esxtop bible every day before I go to bed. Something I however am always struggling with is the “thresholds” of specific metrics. I fully understand that it is not black/white, performance is the perception of a user in the end.
There must be a certain threshold however. For instance it must be safe to say that when %RDY constantly exceeds the value of 20 it is very likely that the VM responds sluggish. I want to use this article to “define” these thresholds, but I need your help. There are many people reading these articles, together we must know at least a dozen metrics lets collect and document them with possible causes if known.
Please keep in mind that these should only be used as a guideline when doing performance troubleshooting! Also be aware that some metrics are not part of the default view. You can add fields to an esxtop view by clicking “f” on followed by the corresponding character.
I used VMworld presentations, VMware whitepapers, VMware documentation, VMTN Topics and of course my own experience as a source and these are the metrics and thresholds I came up with so far. Please comment and help build the main source for esxtop thresholds.

Metrics and Thresholds

Display	Metric	Threshold	Explanation
CPU	%RDY	10	Overprovisioning of vCPUs, excessive usage of vSMP or a limit(check %MLMTD) has been set. See Jason’s explanation for vSMP VMs
CPU	%CSTP	3	Excessive usage of vSMP. Decrease amount of vCPUs for this particular VM. This should lead to increased scheduling opportunities.
CPU	%SYS	20	The percentage of time spent by system services on behalf of the world. Most likely caused by high IO VM. Check other metrics and VM for possible root cause
CPU	%MLMTD	0	The percentage of time the vCPU was ready to run but deliberately wasn’t scheduled because that would violate the “CPU limit” settings. If larger than 0 the world is being throttled due to the limit on CPU.
CPU	%SWPWT	5	VM waiting on swapped pages to be read from disk. Possible cause: Memory overcommitment.
MEM	MCTLSZ	1	If larger than 0 host is forcing VMs to inflate balloon driver to reclaim memory as host is overcommited.
MEM	SWCUR	1	If larger than 0 host has swapped memory pages in the past. Possible cause: Overcommitment.
MEM	SWR/s	1	If larger than 0 host is actively reading from swap(vswp). Possible cause: Excessive memory overcommitment.
MEM	SWW/s	1	If larger than 0 host is actively writing to swap(vswp). Possible cause: Excessive memory overcommitment.
MEM	CACHEUSD	0	If larger than 0 host has compressed memory. Possible cause: Memory overcommitment.
MEM	ZIP/s	0	If larger than 0 host is actively compressing memory. Possible cause: Memory overcommitment.
MEM	UNZIP/s	0	If larger than 0 host has accessing compressed memory. Possible cause: Previously host was overcommited on memory.
MEM	N%L	80	If less than 80 VM experiences poor NUMA locality. If a VM has a memory size greater than the amount of memory local to each processor, the ESX scheduler does not attempt to use NUMA optimizations for that VM and “remotely” uses memory via “interconnect”.
NETWORK	%DRPTX	1	Dropped packets transmitted, hardware overworked. Possible cause: very high network utilization
NETWORK	%DRPRX	1	Dropped packets received, hardware overworked. Possible cause: very high network utilization
DISK	GAVG	25	Look at “DAVG” and “KAVG” as the sum of both is GAVG.
DISK	DAVG	25	Disk latency most likely to be caused by array.
DISK	KAVG	2	Disk latency caused by the VMkernel, high KAVG usually means queuing. Check “QUED”.
DISK	QUED	1	Queue maxed out. Possibly queue depth set to low. Check with array vendor for optimal queue depth value.
DISK	ABRTS/s	1	Aborts issued by guest(VM) because storage is not responding. For Windows VMs this happens after 60 seconds by default. Can be caused for instance when paths failed or array is not accepting any IO for whatever reason.
DISK	RESETS/s	1	The number of commands reset per second.
DISK	CONS/s	20	SCSI Reservation Conflicts per second. If many SCSI Reservation Conflicts occur performance could be degraded due to the lock on the VMFS.

Running esxtop

Although understanding all the metrics esxtop provides seem to be impossible using esxtop is fairly simple. When you get the hang of it you will notice yourself staring at the metrics/thresholds more often than ever. The following keys are the ones I use the most.
Open console session or ssh to ESX(i) and type:

esxtop

By default the screen will be refreshed every 5 seconds, change this by typing:

s 2

Changing views is easy type the following keys for the associated views:

c = cpu
m = memory
n = network
i = interrupts
d = disk adapter
u = disk device (includes NFS as of 4.0 Update 2)
v = disk VM
p = power states

V = only show virtual machine worlds
e = Expand/Rollup CPU statistics, show details of all worlds associated with group (GID)
k = kill world, for tech support purposes only!
l  = limit display to a single group (GID), enables you to focus on one VM
# = limiting the number of entitites, for instance the top 5

2 = highlight a row, moving down
8 = highlight a row, moving up
4 = remove selected row from view
e = statistics broken down per world
6 = statistics broken down per world

Add/Remove fields:

f

Changing the order:

o

Saving all the settings you’ve changed:

W

Keep in mind that when you don’t change the file-name it will be saved and used as default settings.
Help:

?

In very large environments esxtop can high CPU utilization due to the amount of data that will need to be gathered and calculations that will need to be done. If CPU appears to highly utilized due to the amount of entities (VMs / LUNs etc) a command line option can be used which locks specific entities and keeps esxtop from gathering specific info to limit the amount of CPU power needed:

esxtop -l

More info about this command line option can be found here.

Capturing esxtop results

First things first. Make sure you only capture relevant info. Ditch the metrics you don’t need. In other words run esxtop and remove/add(f) the fields you don’t actually need or do need! When you are finished make sure to write(W) the configuration to disk. You can either write it to the default config file(esxtop4rc) or write the configuration to a new file.
Now that you have configured esxtop as needed run it in batch mode and save the results to a .csv file:

esxtop -b -d 2 -n 100 > esxtopcapture.csv

Where “-b” stands for batch mode, “-d 2″ is a delay of 2 seconds and “-n 100″ are 100 iterations. In this specific case esxtop will log all metrics for 200 seconds. If you want to record all metrics make sure to add “-a” to your string.
Or what about directly zipping the output as well? These .csv can grow fast and by zipping it a lot of precious diskspace can be saved!

esxtop -b -a -d 2 -n 100 | gzip -9c > esxtopoutput.csv.gz

Analyzing results

You can use multiple tools to analyze the captured data.

1. perfmon
2. excel
3. esxplot

Let’s start with perfmon as I’ve used perfmon(part of Windows also know as “Performance Monitor”) multiple times and it’s probably the easiest as many people are already familiar with it. You can import a CSV as follows:

1. Run: perfmon
2. Right click on the graph and select “Properties”.
3. Select the “Source” tab.
4. Select the “Log files:” radio button from the “Data source” section.
5. Click the “Add” button.
6. Select the CSV file created by esxtop and click “OK”.
7. Click the “Apply” button.
8. Optionally: reduce the range of time over which the data will be displayed by using the sliders under the “Time Range” button.
9. Select the “Data” tab.
10. Remove all Counters.
11. Click “Add” and select appropriate counters.
12. Click “OK”.
13. Click “OK”.

The result of the above would be:

With MS Excel it is also possible to import the data as a CSV. Keep in mind though that the amount of captured data is insane so you might want to limit it by first importing it into perfmon and then select the correct timeframe and counters and export this to a CSV. When you have done so you can import the CSV as follows:

1. Run: excel
2. Click on “Data”
3. Click “Import External Data” and click “Import Data”
4. Select “Text files” as “Files of Type”
5. Select file and click “Open”
6. Make sure “Delimited” is selected and click “Next”
7. Deselect “Tab” and select “Comma”
8. Click “Next” and “Finish”

All data should be imported and can be shaped / modelled / diagrammed as needed.
Another option is to use a tool called esxplot”. You can download the latest version here.

1. Run: esxplot
2. Click File -> Import -> Dataset
3. Select file and click “Open”
4. Double click host name and click on metric

As you can clearly see in the screenshot above the legend(right of the graph) is too long. You can modify that as follows:

1. Click on “File” -> preferences
2. Select “Abbreviated legends”
3. Enter appropriate value

For those using a Mac, esxplot uses specific libraries which are only available on the 32Bit version of Python. In order for esxplot to function correctly set the following environment variable:

export VERSIONER_PYTHON_PREFER_32_BIT=yes

Limiting your view

In environments with a very high consolidation ratio (high number of VMs per host) it could occur that the VM you need to have performance counters for isn’t shown on your screen. This happens purely due to the fact that height of the screen is limited in what it can display. Unfortunately there is currently no command line option for esxtop to specify specific VMs that need to be displayed. However you can export the current list of worlds and import it again to limit the amount of VMs shown.

esxtop -export-entity filename

Now you should be able to edit your file and comment out specific worlds that are not needed to be displayed.

esxtop -import-entity filename

I figured that there should be a way to get the info through the command line as and this is what I came up with. Please note that needs to be replaced with the name of the virtual machine that you need the GID for.

VMWID=`vm-support -x | grep  |awk '{gsub("wid=", "");print $1}'`
VMXCARTEL=`vsish -e cat /vm/$VMWID/vmxCartelID`
vsish -e cat /sched/memClients/$VMXCARTEL/SchedGroupID

Now you can use the outcome within esxtop to limit(l) your view to that single GID. William Lam has written an article a couple of days after I added the GID section. The following is a lot simpler than what I came up with, thanks William!

VM_NAME=STA202G ;grep "${VM_NAME}" /proc/vmware/sched/drm-stats  | awk '{print $

Troubleshooting Virtual Machine snapshot problems

A nice guide on Troubleshooting VM snapshot problems --> http://is.gd/ckwDc

This troubleshooting guide explains basic concepts about Virtual Machine snapshots and different troubleshooting paths depending on the problem. This guide was designed for ESX3.5 and extra considerations have to be taken if working with ESX3.5i or ESX4(i). The formulas and most of the procedures described in this document were created by Ruben as part of a continuous troubleshooting improvement process.

Ruben is also creator of SnapVMX utility.

While troubleshooting Virtual Machine (VM) snapshot problems sometimes it is important to retrieve a lot of information in order to take the most appropriate decision in accordance with the situation. That collection and arrangement of information may take a long time especially if the VM has many snapshots.


SnapVMX was created to speed up the troubleshooting process bringing you instantaneously all the information that you need to evaluate the situation and take the correct decision, reducing the downtime to the bare minimum needed to solve the problem,
 
Source : Eric Blog

Also Try below VMware KB TV - Consolidating snapshots (VMware KB 1007849) - video below

Top 10 Free vSphere ESX Tools and Utilities

Top 10 Free vSphere ESX Tools and Utilities

http://www.kendrickcoleman.com/index.php?/Tech-Blog/top-10-free-vsphere-esx-tools-and-utilities.html

Hitachi Data Systems has released a free eBook on Storage Virtualization..

Hitachi Data Systems has released a free eBook on Storage Virtualization..
Click on below link to download eBook..

http://www.hds.com/go/dummies/index.html?WT.ac=us_hp_sp1r1

VMware has released the vSphere 4.0 Hardening Guide

VMware would like to announce the availability of the final release of the vSphere 4.0 Security Hardening Guide. This version incorporates the extensive feedback from the VMware community on the previous draft release, which was published in January. We would like to thank all the people who took the time to go through the draft release and provide their comments.

vSphere Hardening Guide provides guidance on how to securely deploy vSphere 4.0 in a production environment. The focus is on initial configuration of the virtualization infrastructure layer, which covers the following:

•The virtualization hosts (both ESX and ESXi)
•Configuration of the virtual machine container (NOT hardening of the guest OS or any applications running within)
•Configuration of the virtual networking infrastructure, including the management and storage networks as well as the virtual switch (but NOT security of the virtual machine’s network)
•vCenter Server, its database, and client components
•VMware Update Manager (included because the regular update and patching of the ESX/ESXi hosts and the virtual machine containers is essential to maintaining the security of the environment)

http://communities.vmware.com/docs/DOC-12306

How to maintain a the same MAC address all the time within your vSphere 4 installation.

In VMware vSphere 4 environement, when you move your VM to another host or the VM has different path on the same host, the MAC adress of the VM is changed.
If you want to guarantee that the same MAC address is assigned to a given virtual machine every time, even if the virtual machine is moved, or if you want to guarantee a unique MAC address for each virtual machine within a networked environment you have 2 choices. You can do it on the VM configuration level or you can do it on the guest level.
On the VM level you can do it via GUI or by editing your VMX file (just make sure that you unregister the VM from vCenter first, otherwise vCenter will overwrite the value) you go to Menu VM > Edit Settings > Network Adapter and you set the radio button on Manual. Then you can assign a static MAC address there between the authorised range by VMware. The MAC address range is:
00:50:56:00:00:00-00:50:56:3F:FF:FF

If in some rare cases you need to keep the same MAC as for exaple on your Physical server (for some software license files tightened to a MAC address for exemple), and the MAC adress is outside of the range, you have the possibility to do it inside of your Windows (linux) VM.
On the Windows VM you do it in the properties of your NIC:
Start the VM and in the Windows system go to Control panel > network connections > Properties

Click the Configure button and go to Advanced Tab where on selecting Locally administered value you are able to enter your own value.

And for linux VM you can try this:
ifconfig eth0 down
ifconfig eth0 hw ether xx:xx:xx:xx:xx:xx
ifconfig eth0 up
There is reference webpage I found about MAC addresses ranges on VMware’s Website here. The page is is for VMware ESX Server 2.1, but it’s still valuable… There might be other resources on that, feel free to post a comment…

Source : www.vladan.fr Feeds

What is FAST? (Fully Automated Storage Tiering) at vBlock (by VMware, EMC, Cisco)

What is FAST? (Fully Automated Storage Tiering) at vBlock
Now available for 3 Flavors (Celera, CX4, Symmetrix)

FAST approach is the Brand new at EMC,
which will automatically move the the LUNs as below..

High I/O LUN’s to Flash Drives (SSD Hdd’s)
Modest I/O LUN’s to F.C Drives
Least I/O LUN’s to SATA Drives

Here are some features, highlights of FAST and how it operates.

• FAST will perform data movement based on IOPS, average I/O size and write percentage.
This is currently true for the Symmetrix V-Max, Clariion CX4 and Celerra NS.

• Three elements that define FAST: Storage Type, FAST policies and Storage Groups.

• FAST is based on user defined -- configuration policies.

• The configuration of FAST is typically done through FAST wizards FAST LUN Migrator for Clariion CX4,
(Symmetrix Management Console) on Symmetrix V-Max and Rainfinity File Management Appliance or VE for Celerra NS.

NOTE: Out of the box thinking by EMC, imagine the flexibility one would have
with a large infrastructure and FAST moving data based on policy.
It’s all about the big picture.

FAST – EMC Hands on Demo



Source : www.storagenerve.com (Full Article Link below)

http://storagenerve.com/tag/vblock/

Feature Compare vSwitch 3.5, vSwitch 4.0, dVswitch 4.0, Cisco Nexus 1000

The following Table is a list of the key features of VMware vNetwork Distributed Switch. For a comprehensive list of VMware vSphere features download the key features summary.

Simplify and Enhance Virtual Machine Networking

• Simplified provisioning and administration of virtual networking across many hosts and clusters through a centralized interface.
• Simplified end-to-end physical and virtual network management through third-party virtual switch extensions for the Cisco Nexus 1000V virtual switch.
• Enhanced provisioning and traffic management capabilities through private VLAN support and bi-directional virtual machine rate-limiting.
• Enhanced security and monitoring for virtual machines migrated via VMware VMotion through maintenance and migration of port runtime state.

Click below --> Read More for Full Article..

Load-balancing Methods (I prefer to call Teaming Methods) --> 1) Originating Port ID Based 2) MAC Hash Based 3) IP Hash Based - Which is best, in real & what supports Actual Load Balance????

Now that we understand the basics, we will move on to the topic at hand, NIC Teaming. Although you can team vNIC's within a VM, we are not going to discuss OS vNIC teaming, but rather physical NIC teaming. You may be wondering why someone would want to team physical NIC's? Well why not! Teaming the NIC's will not only eliminate the single point of failure associated with a single physical NIC, but also provide better overall network throughput - what's not to like!?!

ESX offers 3 different methods for load balancing. However, not all methods are created equal, and only one method offers true load distribution. The 3 load-balancing methods include:

• Route based on the originating port ID (this is the default if not defined otherwise) - Also know as vSwitch port-based load-balancing, this method chooses an uplink based on the virtual port where the traffic entered the virtual switch.

• Route based on source MAC hash - This method chooses an uplink based on a hash of the source Ethernet address.

• Route based on IP hash - This method chooses an uplink based on a hash of the source and destination IP address of each packet.

Click below --> Read More for Full Article (Which one will give Real Load Balancing)

Performance Monitoring of LUN, HBA, VM & for Which Threshold values, you should show concern

The esxtop utility can be used to measure how much I/O is moving across various devices. The esxtop utility is interactive. As such, pressing certain keys changes the view.

Configuring monitoring using esxtop

To monitor storage performance per HBA:

1. Start esxtop by typing esxtop at the command line.
   
2. Press d to switch to disk view (HBA mode).
   
3. Press f to modify the fields that are displayed.
   
4. Press b, c, d, e, h, and j to toggle the fields and press Enter.
   
5. Press s, then 2 to alter the update time to every 2 seconds and press Enter.
   
6. See Analyzing esxtop columns for a description of relevant columns.

 Click below --> "Read More" for Full Article (Tolerable Threshold Values in Real time)..

VMware ESXi 4 Log Files

Source : /www.simonlong.co.uk/blog/

Like most VI Admins, I've been using VMware ESXi quite a lot more lately and I'm slowly coming across things that are different to how they are in ESX. Log files being one of these differences.
With the absence of the Service Console, ESXi presents a slightly different architecture. If you haven't yet read The Architecture of VMware ESXi, I would recommend having a good read through.
Here is the common log file structure in ESX (Source)

 Click below --> "Read More" for Full Article (Log File Geometry & Snippets)..

Cool new HA feature coming up to prevent a split brain situation! in ESX 4 Update 2

Source - www.yellow-bricks.com

One of the most common issues experienced with VMware HA is a split brain situation. Although currently undocumented, vSphere has a detection mechanism for these situations. Even more important the upcoming release ESX 4.0 Update 2 will also automatically prevent Split Brain of H.A!

First let me explain what a split brain scenario is, lets start with describing the situation which is most commonly encountered:

4 Hosts – iSCSI / NFS based storage – Isolation response: leave powered on

When one of the hosts is completely isolated, including the Storage Network, the following will happen:
Host ESX001 is completely isolated including the storage network(remember iSCSI/NFS based storage!) but the VMs will not be powered off because the isolation response is set to “leave powered on”. After 15 seconds the remaining, non isolated, hosts will try to restart the VMs. Because of the fact that the iSCSI/NFS network is also isolated the lock on the VMDK will time out and the remaining hosts will be able to boot up the VMs. When ESX001 returns from isolation it will still have the VMX Processes running in memory. This is when you will see a “ping-pong” effect within vCenter, in other words VMs flipping back and forth between ESX001 and any of the other hosts.

As of version 4.0 ESX(i) detects that the lock on the VMDK has been lost and issues a question if the VM should be powered off or not. Please note that you will(currently) only see this question if you directly connect to the ESX host. Below you can find a screenshot of this question.



With ESX 4 update 2 the question will be auto-answered though and the VM will be powered off to avoid the ping-pong effect and a split brain scenario! How cool is that…

How to troubleshoot Pink Screen on Death (PSOD) in ESX

Source : VMware KB, VMworld PSOD Guide, TechTarget

VMware might not want to get into Blues like Microsoft much famed BSOD (Blue Screen on Death). So they named it as PSOD (Pink Screen on Death).. LOL..

As you know PSOD crash normally could have no shortcut to find the source of problem, VMware tried it's best to make to straight, possible PSOD causes as mentioned below

1) Hardware Faults
2) Host Faults
3) VMM Faults
4) Guest Operating System Faults
5) Application Faults

  How to Capture the PSOD crash dump (By default PSOD dump is saved on /root)

1) type "vm-support" (on # Prompt) without any options. The utility will run and create a single Tar file that will be named  "esx-xxxxxx..tgz".

2) Alternatively, you can generate the same file by using the VMware Infrastructure Client (VI Client). Select  Administration, then Export Diagnostic Data, and select your host (VirtualCenter data optional) and a directory on your local PC to store the file that will be created. 


You may follow these steps to resolve the issue

 Click below --> "Read More" for Full Article

VMware announced vSphere 4.0 Hardening Guide Public Draft Release

Source  : VMware Security Blog
VMware would like to announce the availability of a public draft for the vSphere 4.0 Security Hardening Guide.  This guide represents a new approach to providing security guidance from VMware. As compared with the previous VI3 Hardening Guides, the current guide has the following highlights

• Structure: this version uses a standardized format, with formally defined sections, templates, and reference codes.  The goal is to increase clarity and reduce ambiguity, make it easier to reference individual guidelines, and most of all, enhance the ability to automate guideline enforcement.
• Recommendation levels: in following with the formats used by NIST, CIS, and others, this guide categorizes all guidelines into three security levels.  Instead of recommending a single set of guidelines for all environments, this guide encourages more of a risk-based approach, so that individual administrators can decide which guidelines apply to their environment.

Overall, there are more than 100 guidelines. The guide itself is split into the following major sections: (PDF below)

• vSphere 4.0 Security Hardening Guide: Introduction (REV B)
  
• vSphere 4.0 Security Hardening Guide: Virtual Machines (REV B)
  
• vSphere 4.0 Security Hardening Guide: Hosts (REV B)
  
• vSphere 4.0 Security Hardening Guide: vNetwork (REV B)
  
• vSphere 4.0 Security Hardening Guide: vCenter (REV B)
  
• vSphere 4.0 Security Hardening Guide: COS (REV B)

VMDirectPath (ESX 4 Onwards it's mostly on GUI --> Configuration Examples and Troubleshooting

Now working with Tape Drives, Libraries & 10Gbps devices,
direct from VM's (not from ESX) is piece of cake..

VMware made it more easier through GUI - you don't need to make your hands dirty by editing .VMX.

However, be prepared for few special cases - need to edit .VMX again.

Configuring VMDirectPath I/O pass-through devices on an ESX host - Extract from VMware KB - 1010789 - Click this for link

Purpose

This article provides steps for configuring VMDirectPath I/O direct PCI device connections for virtual machines running on Intel Weybridge and Stoakley platforms.

Resolution

About VMDirectPath I/O pass-through devices

You can connect up to two passthrough devices to a virtual machine. When selecting the devices, keep in mind these restrictions:

• Devices cannot be plugged in after a PCI Bridge.
  
  
• You cannot have two devices in two different contexts (for example, one used by VMkernel and one in pass-through) using the same PCI slot. For example, the dual head NIC is dedicated to the VMkernel OR is available for pass-through. If you select one, the other is automatically selected as well. A dialog informs you why this occurred.

Configuring pass-through devices

To configure pass-through devices on an ESX host:

1. Select an ESX host from the Inventory panel of VMware Infrastructure (VI) Client.
2. On the Configuration tab, click Advanced Settings. The Pass-through Configuration page lists all available pass-through devices.
   
   Note: A green icon indicates that a device is enabled and active. An orange icon indicates that the state of the device has changed and the host must be rebooted before the device can be used.
   
   
3. Click Edit.
4. Select the devices and click OK.
   
   Note: If you have a chipset with VT-d, when you click Advanced Settings in VI Client, you can select what devices are dedicated to the VMDirectPath I/O.
   
5. When the devices are selected, they are marked with an orange icon. Reboot for the change to take effect. After rebooting, the devices are marked with a green icon and are enabled.
   
   Note: The configuration changes are saved in the /etc/vmware/esx.conf file. The parent PCI bridge, and if two devices are under the same PCI bridge, only one entry is recorded.
   The PCI slot number where the device was connected is 00:0b:0. It is recorded as:
   
   /device/000:11.0/owner = "passthru"
   
   Note: 0b is 11 in decimal.

To configure a PCI device on a virtual machine:

1. From the Inventory in VI Client, right-click the virtual machine and choose Edit Settings.
2. Click the Hardware tab.
3. Click Add.
4. Choose the PCI Device.
5. Click Next.
   
   Note: When the device is assigned, the virtual machine must have a memory reservation for the full configured memory size.

Additional Information

For related information, see the VMDirectPath Tech Note at http://www.vmware.com/pdf/vsp_4_vmdirectpath_host.pdf.

VMDirectPath or SCSI Passthru - Making SCSI Card & Devices available to VM's on ESX 3.5.x onwards

Configuring tape drives and media changers on ESX 3.x

Making SCSI Card & Devices available to VM's on ESX 3.5.x onwards (PassThruSCSI)

So that VM (Guest OS) can access SCSI Card & Tape Drives / Medium Changers to fire Backup or Restore (directly from VM) -Currently OEM vendors are not supporting officially - But VMware supports

Details

This article provides instructions for configuring tape drives and media changers so that the virtual machines on ESX 3.x hosts can access the devices. 

Note: Fibre channel attached tape drives are not supported in ESX. For more information, see the SAN System Design and Deployment Guide.

Solution

(VMware KB Article- Click to visit KB

Why should we call VMware will "Optimally utilize the Infrastrusture Resources" - Series1 - Keep your tab on this for my next Series

1) Memory Baloon Driver - Vmmemctl:

(My Understanding in other words - below)

Freeing up the non frequently used / less significant Memory Pages by inflating Vmmemctl Baloon Intentionally creating shortage of memory in specific VM, so that those non frequent Memory Pages Are pushed to Swap file and freed up Memory is under Common Pool (by Vmkernel control - can be shared to other VM's). Once Vmkernel is having enough Memory space and no application is Memory crunch, automatically Vmmemctl Baloon is Deflated, Specific VM has got back it's respective memory.. Very cool feature, 65% of specific VM memory can be freed up by Vmware by default by inflating this Vmmemctl Baloon Technique, However Admin can configure 0%-75% Vmmemctl baloon

Memory Balloon (vmmemctl) Driver

(Extract of VMware Online Library - below)

The vmmemctl driver collaborates with the server to reclaim pages that are considered least valuable by the guest operating system. The driver uses a proprietary ballooning technique that provides predictable performance which closely matches the behavior of a native system under similar memory constraints. This technique effectively increases or decreases memory pressure on the guest operating system, causing the guest to invoke its own native memory management algorithms. When memory is tight, the guest operating system decides which particular pages to reclaim and, if necessary, swaps them to its own virtual disk.

Figure 9-3. Memory Ballooning

Note: You must configure the guest operating system with sufficient swap space. Some guest operating systems have additional limitations. See Swap Space and Guest Operating Systems.

If necessary, you can limit the amount of memory vmmemctl reclaims by setting the sched.mem.maxmemctl parameter for a specific virtual machine. This option specifies the maximum amount of memory that can be reclaimed from a virtual machine in megabytes (MB). See Setting Advanced Virtual Machine Attributes.

2)Transparent Memory Page Sharing

Transparent page sharing is a cool feature of ESX Server that allows VMs to share memory pages that have identical content. If a VM needs to modify the shared data, then the VMkernel creates a new copy for the VM that it can modify. The Operating Systems are not aware that they are sharing memory with other VMs (hence, the name - Transparent page sharing implies)

My Understanding : VM kernel will keep monitoring all VM's Memory Pages and eliminates to occupy the space for redundant copies among various Memory Pages - Instead maintain one copy of common Memory Page ( rest of VM's will have pointer towards this)

VMware vSphere 4 Guided Consolidation

I have added VMware Mylearn Demo Link (Click this Link) - for Guided Consolidation Demo

 (Doesn't work If Pop Up Blocker is there)

Article Extract From : Whugh Griffin Word Press   (Below)

Guided Consolidation is a tool that will allow you to monitor a physical computer and determine it’s potential for adding to your virtual environment. I would highly recommend it for a small to mid sized business looking for some assistance with their P2V process. It has an easy to use interface with a more simplified approach than using the full VMware Capacity Planner utility.
It is free and can be installed from the vCenter installation CD. Once installed, it can be accessed from the vCenter Home Menu. In order to scan a physical computer, you will need to make sure the credentials provided during installation must have administrative permissions on any remote Windows systems selected for analysis. This user account supplied during installation is used to run the “VMware vCenter Collector Service”, a Windows service used to connect to the remote systems.
Once the tool begins to scan the system, it will gather data and display CPU information and utilization, memory information and utilization as well as the computer name. Sometimes it may take up to 1hr before this process begins. Be prepared to allow 24 to 48hrs for this process to complete as Guided Consolidation builds a confidence metric level. Once a high enough confidence level is reached, the status of the system changes to “Ready for consolidation”.
At this point, a consolidation plan is available by selecting the analyzed computer and clicking the “Plan Consolidation” button.
This plan will include a star rating which will identify how likely the physical computer is for virtualization and will even make a recommendation for the target host. The rating system ranges from 1 to 5 stars, with 5 stars indicating the system is a high candidate for the proposed host. From the Consolidation Wizard, you can change several things, the name of the VM, the host being assigned too or even remove a VM altogether from the list.
Multiple systems can be converted to VM’s using this wizard, it’s a very simple process and by the click of one button you are off to the races converting your physical systems to virtual machines.
***Keep in mind that before using Guided Consolidation that a datacenter exists and a host is added to the vCenter Server inventory. ***
I would highly recommend looking at this pdf: http://www.vmware.com/pdf/vsphere4/r40/vsp_40_admin_guide.pdf or picking up a copy of Mastering VMware vSphere 4 by Scott Lowe for more in-depth information on Guided Consolidation.
I hope this gives you a basic understanding of how Guided Consolidation can help you plan a smooth P2V process.

5 things you need to know about VMware vSphere Alarms

By David Davis from http://www.virtualizationadmin.com

Virtualization is an awesome thing but just like any piece of your IT infrastructure, you need to be alerted when something goes wrong (and ideally, before something goes wrong). VMware vSphere has a powerful alerting or notification system built in called "Alarms" (call them whatever you want but if you want to use them in vSphere, you should start calling them "alarms"). Alarms can be configured to tell you when specific events, conditions, or states occur within the vSphere inventory.

Let's learn the 5 most important things you need to know about vSphere alarms.

1. vSphere has 33 pre-configured and enabled alarms
2. Alarms trickle down the vSphere inventory hierarchy
3. vSphere has a Triggered Alarms and an Alarm Definitions View
4. vSphere has 8 Alarm monitoring types
5. An Alarm is defined by with a type, trigger, and action

In point #5, we learn that creating a new alarm is easy by following my simple 7 steps. Overall, it is crucial for vSphere Admins to understand how alarms work in order to properly monitor their virtual infrastructure and to be alerted of issues that need to be resolved. I encourage you to spend a few minutes working with vSphere alarms!
Step by Step Guide to learn above 5 Things --> Link here from www.virtualizationadmin.com

Cisco Nexus 1000V Switch Seminar Series

The Cisco Nexus 1000V Switch delivers VN-Link services to virtual machines hosted on its server. It takes advantage of the VMware vSphere framework to offer tight integration between server and network environments, and to help ensure consistent, policy-based network capabilities to all servers in your data center.

Learn more about this software switch at the Nexus 1000V Switch Spring 2010 Seminar Series. The series has two tracks: Sales and Technical.

Topics include:

• Nexus 1000V Switch Business Impact and Return on Investment
• Basic Nexus 1000V Switch Features
• Accelerating Data Center Virtualization with Nexus 1000V Switch
• Advanced Nexus 1000V Switch Features
• Nexus 1000V Customer Panel
• Virtualize DMZ with Nexus 1000V Switch
• Analyst Panel Roundtable Discussion: Nexus 1000V Switch
• Approach Payment Card Industry (PCI) Compliance with Nexus 1000V Switch
• Ecosystem Partners & Products
• VN-Link and the Future of Virtual Networking
• Channel Partner Roundtable Discussion
• Interoperability with VMware Products
• Infrastructure as a Service Reference Architecture
• Cisco Nexus 1010 Virtual Services Appliance
• Advanced Networking in a Virtualized Environment