Tuesday, 13 December 2016

VCAP6-DCV Design Objective 2.4

We already had a detailed discussion about VCAP6 - DCV Design exam, where we discussed about the Path we need to follow and what are the objectives that we need to take care, If in case you missed it here is the link for your reference Kick Start Your Journey Towards VCAP6-DCV Design.

We have also seen VCAP6-DCV Design Objective 1.1, VCAP6-DCV Design Objective 1.2 and VCAP6-DCV Design Objective 1.3 in which we discussed about Business and Application Requirements,Risks,Constraints, Assumptions and also discussed how to map the business requirements into VMware vSphere Logical Design and also talked about mapping service dependinces here are the links for your reference in case you missed it VCAP6-DCV Design Objective 1.1VCAP6-DCV Design Objective 1.2 , VCAP6-DCV Design Objective 1.3 , VCAP6-DCV Design Objective 2.1VCAP6-DCV Design Objective 2.2.

In our recent post VCAP6-DCV Design Objective 2.3 related to this VCAP6-DCV Design series we also talked about how we can build the availability requirements into a vSphere logical design.

Another good week came to an end was involved with another VMware vSphere 6 Design and Deploy class lot of interesting questions to answer and lot of new vSphere Design examples to share.

Well if in case i missed it earlier and you guys already not aware about the Design exam simulator available at vmware.com/education here is the link for your reference Practice Exam which will give you a brief about how the VCAP6-DCV Design exam looks like.

Objective 2.4 - Build Manageability Requirements into a vSphere 6 Logical Design

Skills and Abilities
  • Evaluate which management services can be used with a given vSphere Solution.
  • Differentiate infrastructure qualities related to management.
  • Differentiate available command line-based management tools (PowerCLI, vMA etc.)
  • Evaluate VMware Management solutions based on customer requirements.
  • Build interfaces into the logical design for existing operations practices.
  • Address identified operational readiness deficiencies
  • Define Event, Incident and Problem Management practices.
  • Analyze Release Management practices
  • Determine request fulfillment and release management processes.
  • Determine requirements for Configuration Management
  • Define change management processes based on business requirements.
  • Based on customer requirements, identify required reporting assets and processes
How to Prepare
Time to begin with VCAP6-DCV Design Objective 2.4 which will help us to proceed further with our ultimate goal VCAP6-DCV Design exam, will be focussing on the management services to be included in the design.

When working towards design decisions towards management solution to be included in the design will start with update manager as it is one of the key aspect to be consider when thinking about infrastructure manageability and the design decision follows with the deployment model to be used for update manager ? 

Depending upon the environment we can go with All in one wherein the update manager will share the database with vCenter Server and vSphere update manager will be installed on the vCenter Server host machine, another option available for us is to choose the medium deployment model where we can go with a separate database instance for vSphere update manager however installing the vSphere update manager on vCenter Server host and the last option is large deployment model installing vSphere update manager on separate host and choosing a separate database instance for update manager.

When dealing towards the update manager there are few more design decisions that we need to think about -
  • How we want to configure the download settings / Source of images - VMware, VMware Partner / Custom Images
  • Which baselines should be used static/dynamic?
  • How should ESXi and vCenter Server settings should be configured?
vSphere update manager deals with patching / update / bug fixes of ESXi, Appliance, VMware tools, VM's Hardware version means we still have to find another way to update guest os and applications which should also be included in design decisions pertaining towards infrastructure manageability.

Either we can go with existing tools and method the customer is using as it requires less training to resources, moreover the tools they are currently familiar with may require little modification to work in a Virtual Environment.

Another option which can be used is to make use of VMware vRealize Configuration manager which can help us automating the operating system and software provisioning and patching.

Few more important design decisions to take care of when working towards infrastructure manageability requirements and fitting them to our logical design.

  • What management tools should be used for troubleshooting and performance monitoring, and day to day operations this question helps us define the scope of various other tools which can make our life easier when it comes to troubleshooting we can make use of (vRealize Log insight) as it provides us a better insight to logs and for monitoring we can use alarms, performance charts and command line management tools or we can also go with (vRealize operations manager) for day to day operations we use vSphere Web client and if in case the business requires for automating the day to day operations we can include vSphere Management Assistant and vSphere Power CLI.
  • How we would be working towards the template and snapshot management are two another important factors to be considered, whether content library should be used for the ease of template management or not and as far as snapshots are concerned we cannot consider them as backup however we can ensure they are included as part of the change management process and might requires management approval.
  • ESXi installation would be taken care through native installation method or the entire process should be automated scripted automated installation definitely reduces the overall time of deployment and also avoid configurations errors however whether it should be included in the design in the first place is a question depending upon the size of the environment we are dealing with and how comfortable the business is when it comes to scripted installation.
  • Design decisions should also be taken care related to CIM and SNMP ensuring a proper SNMP trap destination is configured which can affect the information being sent to wrong destination.
  • Database retention policies is another important design decision to be included as they help us to decide when to delete the vCenter Server related tasks and events, make sure you have a proper business justification of going with longer retention period as it provides a better scope of troubleshooting however also needs a bigger database.
Key Note : As part of this objective when working closely towards achieving the design goal it's not only the management tools/Installation related design decision that we need to take care.

We also need to document design decisions related to the ITIL standards aligned with organization policies which talk about Incident, Change, Release management and all the updates/upgrades can be bought up in the same CAB call and can be discussed with various stakeholders / implementation teams a very good example of the same is discussed in https://communities.vmware.com/docs/DOC-11457

Thursday, 8 December 2016

Vembu BDR - Product Review







Dedicated couple of weeks working with product development / marketing team of Vembu Technologies which is a privately held, information technology company that specializes in developing software products in Backup, Disaster Recovery and cloud storage domains. Vembu’s products serve data center IT-Administrators in small and medium businesses managing VMware, Microsoft Hyper-V and Physical Server environments and was founded in 2002 and tested out some cool and exciting features.
Vembu’s latest offering includes, Vembu BDR Suite v3.6.0 that provides enterprise-level features for Small & medium businesses thus providing them an edge in the market and help them in cutting overhead costs. It is truly comprehensive in nature for providing Backup, Replication & Disaster Recovery across varied environments like VMware VSphere, Microsoft Hyper-V, Windows IT environments, Linux, Mac and so on. It provides Image backup as well as application level, File level Backup, for endpoints, for SaaS applications like Office365 and Google Apps
The products under Vembu BDR Suite are:
Vembu VMBackup
The most reliable, simpler and affordable Backup & DR product for virtualized environments, Vembu VMBackup provides agentless Vmware vSphere & Microsoft Hyper-V Backups with as low as $360 Per Cpu Socket Per annum for VMware VM’s and $240 per Cpu Socket per annum for VMbackup for Hyper-v  thus making it a handy product for IT admins for their virtual environments.
Vembu ImageBackup:
With entire Image-level Backup for Windows Servers & Workstations, File-level Backup, Bare-metal Recovery, Migration options from Physical to Virtual environments, Vembu ImageBackup is a comprehensive Backup & Disaster Recovery for Windows IT environments. Vembu ImageBackup supports from Windows Server 2003 SP2 upto Windows Server 2012 R2 and from Windows XP SP2 upto Windows 10. Furthermore, Desktops/Laptops Backup is completely free. For Servers, it is as low as $180 per server/annum per server.
Vembu NetworkBackup:
Vembu NetworkBackup is designed for small & medium businesses to protect critical business data across file servers, application servers, workstations and other endpoints in Windows & Linux environments. Application & File Backup in workstations is completely free. The Backup license fee is $150 per server application per annum, while it is $60 per file server per annum 
Vembu OnlineBackup:
Vembu OnlineBackup is a user-friendly backup solution that lets you backup your Business Critical Data to our Secure Vembu Cloud. It includes File Backup, Server Backup, Application backup for MS Exchange​, MS SQL​​​, MS SharePoint & MS Active ​Directory​ with Granular restores. For OnlineBackup of application servers, the license fee is $72/application/annum, for OnlineBackup of file servers, the license fee is $24/server/annum, completely free for workstations with $0.20/GB/month as Vembu cloud storage fee. 
Vembu SaaSBackup:
With SaaS applications taking over the CRM & other businesses, there are associated threats of data loss with it. Vembu SaaSBackup is designed to protect mails, drives & contacts in SaaS applications like Office365 and Google Apps with faster recovery options and rich UI. The cost for the same is $24/user/annum for Office365 and Google Apps respectively with $0.20 per GB/month as cloud storage fee.
Apart from the products under Vembu BDR suite we also have other Add - On Products 
Vembu Offsite DR v3.6.0 which offers added data protection, allowing users to replicate data to their very own data center from backup server with a cost of $90 per cpu-socket/annum for VMware VM’s and $60 per cpu-socket/annum for Hyper-v.
Vembu CloudDR v3.6.0 offers added data protection by allowing you to transfer data to Vembu’s Cloud. There are multiple options for restores including booting a live VM on our cloud, anytime anywhere restore via internet or restored data can be downloaded to USB drive and shipped with a cost of $0.20 per GB/month both for VMware and Hyper-v environments.
Vembu BDR360 is the centralized monitoring and management portal that provides end to end visibility to all your IT environment backed up using the Vembu BDR Suite products which is available for purchase for as low as $60 per cpu-socket/annum for VMware and $40 per cpu-socket/annum for Hyper-v.
Now that I was already fascinated about the pricing of Vembu Products thought of testing out some features and functionalities around Vembu BDR and take my experience with the product to whole new level, first thing first downloaded the executable file of Vembu BDR and logged in as admin, configuring the time zone was the first step which later followed by integration of the environment we are planning to backup.
Next step was to integrate the environment we want to backup by either providing the details of our vCenter Servers or Microsoft Hyper-V by adding our Hyper-v hosts and the Physical image if in case we wish to backup physical servers and desktop by installing Vembu Image Backup Client Installer.  
Proceeded further with VMware vSphere integration wherein I started by adding the Unique Vembu BDR ID - Provide Machine Name followed by the FQDN of my vCenter Server along with username and password and was able to fetch the details of vCenter Server and it’s associated hosts and Virtual Machines.
From the inventory loaded selected one of my Virtual Machine named Linux-a-10 and proceeded further testing some features well I personally liked this one which provided me the options to exclude disks from that Virtual Machine which I don’t want to backup or maybe I only want to backup the system disks.
Definitely a cool feature which made me think of recent use case wherein I was dealing with one of my customer’s environment in which they have a specific business requirements of including only the system disks and to exclude other disks as they contains static web pages which never changes.
The virtual machine which I selected had only the system disks so proceeded further without excluding any disks. 
When selecting application aware image process we need to ensure some prerequisites 
1. Backup jobs enabled with application-aware image process option requires that your guest OS has latest VMware Tools, all the latest packages and patches installed.
2. Its recommended to configure Application Servers in separate backup job as application aware image process option can be enabled at backup job level only.
3. To perform application-aware image processing, you must provide guest OS login credentials for the selected VM(s) running MS Exchange server, MS SQL Server, MS SharePoint Server, MS Active Directory.
Next task in the list was to configure retention so scrolled down with the available options we have when configuring retention, well we got two options Basic Retention where in we can specify how many retention points we need to opt out for and when the retention count for the incremental count is reached older increments will be purged and the latest incremental will be retained and Advance Retention option which help us to choose and configure the retention policy daily, weekly and monthly. 
Now that we took the backup of the virtual machine it’s time to proceed further and checkout the features available with restore, as a matter of fact Vembu team really surprised me by showing a lot variety of options to select from.
Instant VM recovery -  This option help us to Recover Virtual Machines as Ready state which means the Virtual Machines would be instantly available helping us in maintaining the business continuity with minimal amount of downtime by specifying the target server and the target datastore.
Live Recovery to ESXi Server- Helps us to restore the backed-up virtual machine directly to target ESXi hosts where we can also perform partial VM restore at disk level by selecting the vCenter Server datastore.
File level Recovery – Option auto attach backup to Disk management in the local machine which allows instant access to the backed up data and give us a way to perform instant file recovery.
Disk Level Recovery - Restores the VM backup at disk level where backed-up disks can be restored to target VM’s by specifying the details about the target VM.
Download – This is one of another cool feature which provides a multi format restore for any images backup be it physical/ virtual.
My Final Thoughts – It was time to talk about my final thoughts about Vembu BDR as a solution and there are couple of points which I would like to talk about and should be taken care when planning to consider your backup and recovery vendor.
  • The Backup and Recovery Solution should be simple enough to setup and manage which we have recently seen when we have installed the Vembu BDR and as a matter of fact, I liked the GUI which provides us enough capability that we can manage VMware/ Hyper-v Environment from a single console.

    Thinking from an administrator perspective who is responsible to take care of both the Hyper-V and VMware vSphere Environment can now work on a single console rather than hopping in and out of various consoles.
  • Backup and Recovery solution should be capable enough of creating multiple backup jobs which can be executed in parallel by providing the same performance for each of the backup job executed, well I tried to test the same and was focusing on the performance of each jobs being executed in parallel and I was surprised by the amount of time taken by both the jobs for completing the full backup of a windows VM and Linux VM as both of the jobs were executed within few minute and one job hasn’t impacted the overall performance of second job being executed in parallel. 
  • Another key note to consider when thinking about Backup and Recovery Solution should be the capability of the solution to provide backups of file servers and enterprise applications such as SQL and Exchange which is one of another feature provided by Vembu BDR application aware image processing where we can think about few prerequisites and move forward by creating any additional backup job.
  • Pre and Post Sales support is another key area where we should look into when thinking about working with Backup and Recovery solution vendor and for this point Vembu Product/Marketing team deserves a Five Star as they have been very helpful throughout the product training/testing phase/. 

**Please note that this review was sponsored by Vembu

Tuesday, 22 November 2016

What's New - Nakivo Backup and Replication 6.2

We have already dedicated couple of articles related to Nakivo Backup and Replication v6.1 wherein we have seen the architectural components and also talked about new features available in Nakivo Backup and Replication v6.1 here is a link for your quick reference Demystifying Nakivo Backup and Replication v6.1

In our last post related to Nakivo Backup and Replication Series we also discussed about 

Backup/Recover Active Directory Objects with Nakivo Backup and Replication v6.1 in case you missed it here is the link for your quick reference 
Backup/Recover Active Directory Objects with Nakivo


Apart from testing the backup and recovery related functionalities using Nakivo Backup and Replication v6.1 we also had a detailed discussion on Replicating Virtual Machines here is the link for your reference Replicate VM's with Nakivo Backup & Replication

In our last blog post related to Nakivo Series we also talked about working with Nakivo Backup and replication appliance 

Dedicated this article to understand what's new with Nakivo Backup and replication 6.2 which was announced by NAKIVO on october 13th 2016 which help us by providing backup, replication, and recovery of paid EC2 instances sold through AWS Marketplace.




When Selecting Nakivo backup and replication Free edition from AWS Market place the only fee we are suppose to pay is for our EC2 instance running in AWS which may vary depending on the EC2 Instance type we selected during the launch process. 

Didn't want to get overcharged for the instance being deployed for testing purpose so thought of going with t2 Micro running with 1Gib Memory and 1 Virtual Core. Good for testing :-)


Well as the name suggests here BYOL (Bring your Own License) is available for those customers who already have purchased the licenses.


As the cost estimator says we have to think about the cost of already purchased license and the cost of the AWS based on the instances we have selected.



When Selecting the option for Nakivo Backup and replication Pro for 10 instances we have to pay $49 Per month + AWS infrastructure charges for EC2 instances.



Selected the same t2 micro EC2 instance with 1 Gib Memory and 1 Virtual Core to see the difference in cost estimator as this time we have selected the option for 25 instances hence a $ 99 Per month would be the subscription fee for backup of AWS EC2 instances apart from the AWS Infrastructure charges.

** Prices Mentioned above may change kindly refer the AWS market place for the latest pricing information.

Keynote: By Selecting one of the above options from AWS market place we can create and maintain the identical copies of our EC2 instances.

When it comes to backup of AWS EC2 instances using Nakivo Backup and Replication v6.2 we can select the same AWS region or a different AWS region or it could be done directly to on premises locations.

Sunday, 6 November 2016

Back to Basics - Part 12 Distributed Resource Scheduler

In our couple of blog post related to Back to Basics Series we discussed about Virtual Machine Files (Part1), Standard Switches (Part2), vCenter Server (Part 3),Templates (Part4) vApp (Part 5), Migration (Part 6),Cloning (Part 7), Host Profiles (Part 8), Virtual Volumes AKA VVOL's (Part 9) Fault Tolerance (Part10) and Distributed Switches (Part 11) and we also discussed about the various tasks related to building Home Lab Part1Part 2Part 3,Part 4 Part 5.

It's been so long i have updated any article related to back to basics series so thought of dedicating this article to understand functionalities of Distributed Resource Scheduler a.k.a DRS.

But before we begin and talk about DRS let's think about life without DRS for a minute

Well thinking from an administrator perspective how difficult it would be to keep an eye on resource consumption of our ESXi hosts running in our HA Cluster.

Or in another words how difficult it would be to ensure that all my Virtual Machines running in HA cluster are balanced across the available number of ESXi.


Certainly life without DRS is hard to imagine as it would require a lot of manual intervention in terms of balancing the Virtual Machines in cluster.

Role of VMware vSphere High Availability is only to restart our Virtual Machines but not to load balanced them ! Load balancing requests would be taken care by DRS so let's find out how DRS plays an important role in our VMware vSphere environment.

10 Things You Need to Know about Distributed Resource Scheduler.
  • vSphere DRS can be created or can be enabled on our existing vSphere HA and VSAN Clusters.
  • vSphere DRS Works best when our Virtual Machines meets the requirements of VMware vSphere vMotion including shared storage, and vMotion Network.
  • While creating the vSphere DRS cluster we can select the automation level which helps us in understanding whether the vSphere DRS should generate migration recommendations or automatically place the Virtual Machines on the host.
  • Automation levels includes Manual - When we power on the Virtual Machine vSphere DRS lists recommendations where to place the Virtual Machine.However when we select Partial Automated - The Minute Virtual Machine is powered on vSphere DRS will place it on best suited host and if in case the cluster becomes imbalance vSphere DRS will help us with the recommendations so as we can manually migrate the Virtual Machine. Fully Automated - As the name suggests will place the Virtual Machine on best suited host at the time of Power On and will migrate the Virtual Machine if in case the cluster is imbalanced.
  • Automation levels for individual Virtual Machines can be selected if in case we wish to override the automation level set on the entire DRS cluster.
  • Another important option available in DRS settings is migration threshold provided with various levels (Level 1 Conservative, Level 2 (Applying Priority 1 and Priority 2 Recommendations), Level 3 Default (Applying P1,P2 and P3 Recommendations) , Level 4 - (Applying P1,P2,P3 andP4 Recommendations) and Level 5 Aggressive (Applying all the recommendations) ).
  • In vSphere DRS cluster we can make use of Affinity (Keep Virtual Machines Together) and Anti Affinity rules (Keep Virtual Machines Separate).
  • We can also make use of DRS Groups which could be a group of virtual machines or group of hosts assisting us in defining Virtual Machine to Hosts affinity rules.
  • Virtual Machines to host affinity rules majorly includes three important components (Virtual Machine DRS Group, Host DRS Group, and specification including whether the rule is a preferential should or is a required rule must ).
  • Distributed Power Management is another feature provided by vSphere DRS which uses Wake-on-LAN, IPMI, or iLO to power on hosts and is either off (Wherein vCenter Server will not provide any power management recommendations) or works in Manual mode (Where vCenter Server will recommend evacuating the host virtual machine) and Automatic mode ( Where vCenter Server will automatically execute any power management related recommendations).

Saturday, 5 November 2016

Working with Nakivo Backup and Replication Appliance

We have already dedicated couple of articles related to Nakivo Backup and Replication v6.1 wherein we have seen the architectural components and also talked about new features available in Nakivo Backup and Replication v6.1 here is a link for your quick reference Demystifying Nakivo Backup and Replication v6.1

In our last post related to Nakivo Backup and Replication Series we also discussed about 

Backup/Recover Active Directory Objects with Nakivo Backup and Replication v6.1 in case you missed it here is the link for your quick reference 
Backup/Recover Active Directory Objects with Nakivo


Apart from testing the backup and recovery related functionalities using 
Nakivo Backup and Replication v6.1 we also had a detailed discussion on Replicating Virtual Machines here is the link for your reference Replicate VM's with Nakivo Backup & Replication
Dedicated this article to understand the deployment of Nakivo Backup and Replication appliance which is available as-

Full Solution

This Virtual Appliance contains all components of NAKIVO Backup & Replication including Director, Transporter, and Backup Repository. Download this Virtual Appliance if you want to do a new installation of the product and keep all (or some) of your backups on the Virtual Appliance.

Full Solution without Backup Repository

This Virtual Appliance contains the key components of NAKIVO Backup & Replication: Director and Transporter, but does not include the Backup Repository (a new one can be created later). Download this Virtual Appliance if you want to do a new installation of the product and do not want to keep backups on the Virtual Appliance.


Transporter

This Virtual Appliance contains only the Transporter component of NAKIVO Backup & Replication. Download this Virtual Appliance if you have already installed the Director and want to install an additional Transporter to distribute workload or run jobs across WAN.


This Virtual Appliance contains the Transporter and Backup Repository components of NAKIVO Backup & Replication. Download this Virtual Appliance if you have already installed the Director and want to install an additional Transporter and keep backups on it.


This Virtual Appliance contains only the Director component, which is deployed in the multi-tenant mode. Download this Virtual Appliance if you want to provide BaaS, RaaS, or DRaaS.

I have been using the windows based installer solution for entire testing in my Home lab so thought of deploying the Virtual Appliance Full Solution and integrate the same with my vSphere environment.



Downloaded the full version and then using web client deployed the OVA on one of my ESXi host.

It's time to proceed further and configure the settings of the recently installed appliance by opening the console.


When working with the appliance we can configure network settings which talks about providing the Hostname IP address assignment Static or DHCP.

Backup Storage settings provides us the options for attaching a new disk, refresh the list of available disks on the current page, select the new not used disk to be used for backup storage.




Time and Time Zone settings helps us to change time and time zone for our Nakivo backup and replication appliance.

System Performance gives us the overall performance in terms of CPU and Memory Utilization and another important feature provided in system performance is to make use of TOP command which will help us in providing the list of tasks running.



Next settings/option in our list is Software updates which helps us in updating the current software by uploading the updates in the update directory /opt/nakivo/updates.

Nakivo Command Console where we can use Nakivo commands either locally or remotely via SSH. Below i have provided an example of running a command and it's output.


Once all the required settings are completed from command line we can proceed further and connect Nakivo backup and replication appliance by providing https://Ip address of appliance Virtual Machine:4443 in our browser.


Wednesday, 26 October 2016

vSphere On-disk Metadata Analyzer

vSphere On-disk Metadata Analyzer (VOMA) is a utility which helps us in performing VMFS file system metadata checks

We might need to check metadata consistency of a file system when we experience problems related to storage outages or could be when we performed a disk replacement we might see errors in vmkernel.log file.

How does the error looks like well i haven't received this error in my Home Lab environment but when delivering VMware vSphere troubleshooting workshop class one particular troubleshooting topic talks about metadata consistencies and the troubleshooting steps we need to take to work with this kind of problem.

So thought of checking any related KB articles which talks about the same got one KB article 2036767 which talks about vSphere On-disk Metadata Analyzer (VOMA) to check VMFS metadata consistency.

vmkernel: 25:21:39:57.861 cpu15:1047)FS3: 130: <START termserv2-5160fe37.vswp>
vmkernel: 25:21:39:57.861 cpu15:1047)Lock [type 10c00001 offset 52076544 v 69, hb offset 4017152
vmkernel: gen 109, mode 1, owner 4a15b3a2-fd2f4020-3625-001a64353e5c mtime 3420]
vmkernel: 25:21:39:57.861 cpu15:1047)Addr <4, 1011, 10>, gen 36, links 1, type reg, flags 0x0, uid 0, gid 0, mode 600
vmkernel: 25:21:39:57.861 cpu15:1047)len 3221225472, nb 3072 tbz 0, zla 3, bs 1048576
vmkernel: 25:21:39:57.861 cpu15:1047)FS3: 132: <END termserv2-5160fe37.vswp>vmkernel: 0:00:20:51.964 cpu3:1085)WARNING: Swap: vm 1086: 2268: Failed to open swap file '/volumes/4730e995-faa64138-6e6f-001a640a8998/mule/mule-560e1410.vswp': Invalid metadata
vmkernel: 0:00:20:51.964 cpu3:1085)WARNING: Swap: vm 1086: 3586: Failed to initialize swap file '/volumes/4730e995-faa64138-6e6f-001a640a8998/mule/mule-560e1410.vswp': Invalid metadata
cpu11:268057)WARNING: HBX: 599: Volume 50fd60a3-3aae1ae2-3347-0017a4770402 ("<Datastore_name>") may be damaged on disk. Corrupt heartbeat detected at offset 3305472: [HB state 0 offset 6052837899185946624 gen 15439450 stampUS 5 $

Before running VOMA ensure all virtual machines on the affected datastore are powered off or migrated to another datastore.

It's time to fetch out the name and partition number of the device which backs the VMFS datastore that we are planning to check.

It can be done using esxcli storage vmfs extent list command after connecting to your ESXi host through putty.



Now that we have got the details we require to run vSphere On-disk Metadata Analyzer it's time to run the same.

*Note: Installation/Configurations/Specifications methods used here has been Tested in My Home Lab Nested Environment.

 voma -m vmfs -f check -d /vmfs/devices/disks/eui.5adcee56739fb3ea:1

Where eui.5adcee56739fb3ea:1 refers to device name and the partition.



***** We are able to run the VOMA successfully as there is no problems with data consistency but if incase you may have metadata consistency issues in your environment you may find errors  (Error: Missing LVM Magic. Disk doesn’t have a valid LVM Device Error: Failed to Initialize LVM Metadata)

We can also run the above command by specifying the log file where we want to store the output and send it to VMware support team.
*****When the corruption is irreversible, VMware recommends us to restore the datastore files from a backup.

In my environment i stored the output in output.txt file created in temp directory by using the same command as mentioned above with the name and location of the file.

 voma -m vmfs -f check -d /vmfs/devices/disks/eui.5adcee56739fb3ea:1 -s /tmp/output.txt


Tuesday, 25 October 2016

ESXi Frequently Disconnects from vCenter Server

Recently in my Home Lab Environment i noticed one of my ESXi hosts frequently getting disconnected from vCenter Server. 

Before we proceed further with troubleshooting we need to understand that ESXi host share the heartbeats (UDP 902) with vCenter Server to inform the vCenter Server that it is accessible over management network so it seems to be the problem with the heartbeat packets which are getting dropped,blocked or lost between the vCenter Server and the ESXi host.

Now as part of troubleshooting process we may come up with many possible cause for this problem as we have three different layers involved i.e (vCenter Server, ESXi and hardware)

First layer first vCenter Server one possible cause could be windows firewall rules which was enabled on vCenter Server System and was blocking UDP Port 902.

At ESXi layer we may suspect that ESXi host is not using port 902 for receiving the heartbeats rather a different port is configured or it could be the Internal ESXi firewall which is blocking that port.

At the bottom layer Hardware Layer we are suspecting that the network between my ESXi hosts and vCenter Server is congested.

In my Home Lab i am using windows based vCenter Server so checked firewall settings to be on safer side i disabled Windows Firewall because there were no ports configured.


Now time to check ESXi host if it was using the default port 902 or any other port not sure if i changed as part of some testing.

*Note: Installation/Configurations/Specifications methods used here has been Tested in My Home Lab Nested Environment.


As suspected it wasn't using the default port 902 so now i got two ways to fix this problem either add a firewall rule to ESXi firewall to allow the port being used or change the port back to 902.

Changing the port back to default 902 can be done by editing the vpxa.cfg file residing at /etc/vmware/vpxa/.

For creating a firewall rule for ESXi host to allow other ports i referred KB Article 2020100 which talks about the details we need to enter when creating Heartbeat.xml file and adding the rules into the file.
   

We can make use of command vi /etc/vmware/firewall/hearbeat.xml which will create heartbeat.xml file if not already created and will also edit the file for you.

Now that we have find the problem and we fixed it as it was the issue with one of my ESXi what if it was't the problem than the last resort of troubleshooting was to check the hardware i.e whether if network congestion exist between my vCenter Server and ESXi host.

Either we can make use of some third party tools like Wireshark to Analyze the live traffic  or we can also make use of ESXTOP command line utility to analyze traffic which can give us an insight about the congestion if any in our network.