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How to Fix VMware ESXi Virtual Machine 'Invalid Status'

Posted in Virtualization & VM Backup

In this article, we'll show you how to deal with VMs which are reported to have an Invalid Status as shown in the screenshot below. This is a common problem many VMware and System Administrators are faced with when dealing with VMs. We'll show you how to enable SSH on ESXi (required for this task), use the vim-cmd to obtain a list of the invalid VMs, use the vim-cmd /vmsvc/unregister command to unregister - delete the VMs and edit the /etc/vmware/hostd/vmInventory.xml file to remove the section(s) that references the invalid VM(s).

The Invalid Status issue is usually caused after attempting to delete a VM, manually removing VM files after a vMotion, a problem with the VMFS storage or even after physically removing the storage from the ESXi host e.g replacing a failed hdd.

esxi vm machine invalid status

Another difficulty with VMs stuck in an Invalid Status is that VMware will not allow you to remove or delete any Datastore associated with the VM e.g if you wanted to remove a HDD. For safety reasons, you must first remove or migrate the affected VM so that there is no VM associated with the Datastore before VMware allows you to delete it.

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The screenshot below shows ESXi failing to delete datastore 256G-SSD - which is used by VM FCX-ISE1 above, now reported to be in an Invalid Status:

esxi vm unable to delete datastore

As most System Administrators discover in these situations - they are pretty much stuck and the only way to remove the VM, now marked as 'Invalid', is to delete it as the Unregister option cannot be selected when right clicking on top of the VM:

esxi vm invalid status delete unregister option unavailable

Notice in the screenshot above how the Unregister or Delete menu options are not available.

The only method to delete this VM is to use the SSH console on the ESXi host and execute a number of commands. This implies that SSH has been enabled on the ESXi host.

Read our quick guide on “How to enable SSH on an ESXi host” if SSH is not enabled on your ESXi host.

Once ssh is enabled, connect to your ESXi host with any ssh client such as e.g Putty using your ESXi root credentials, then use the vim-cmd with the following parameters to obtain a list of the invalid VMs:

How to Enable SNMP on VMware ESXi Host & Configure ESXi Firewall to Allow or Block Access to the SNMP Service

Posted in Virtualization & VM Backup

In this article we will show you how to enable SNMP on your VMware ESXi host, configure SNMP Community string and configure your ESXi firewall to allow or block access to the SNMP service from specific host(s) or network(s)

Enabling SNMP service on a VMware ESXi host is considered mandatory in any production environment as it allows a Network Monitoring System (NMS) access and monitor the ESXi host(s) and obtain valuable information such as CPU, RAM and Storage usage, vmnic (network) utilization and much more.

how to enable snmp on esxi host

Furthermore, an enterprise grade NMS system can connect to your VMware infrastructure and provide alerting, performance and statistical analysis reports to help better determine sizing requirements but also identify bottlenecks and other problems that might be impacting the virtualization environment.

Execution Time: 10 minutes

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Concerned about your VM machines and data? Download now your Free Enterprise-grade VM Backup solution

Enable SSH on ESXi

First step it to enable SSH on ESXi. This can be easily perform via the vSphere client, ESXi console or Web GUI. All these methods are covered in details in our article How to Enable SSH on VMware ESXi.

Enable and Configure ESXi SNMP Service

Once SSH has been enabled, ssh to your ESXi host and use the following commands to enable and configure the SNMP service:

Complete Guide to Netflow: How Netflow & its Components Work. Netflow Monitoring Tools

Posted in Netflow

This article will cover the basics of Netflow, including its use cases, Netflow supported devices, Netflow history, and variants. We’ll also dive into the technical details of how the Netflow protocol works, including the Netflow ports, and the various Netflow versions. This will lead onto coverage of the various Netflow components, including the Netflow Exporter, Netflow Collector, and Netflow Analyzer, with some brief coverage of its main competition. Here’s the full breakdown of what’s covered:

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Introduction to Netflow – What is Netflow Used for?

Visibility plays a key role in the maintenance and security of any network. With it, admins can identify issues, discover non-compliant users, refine their provisioning, and more. Netflow is a protocol developed by CISCO that fulfils this purpose, letting interested parties understand network patterns and protocol distribution, while supporting more granular data like IP service type for diagnosis.

Its relatively low overhead and trusted history means that Netflow is still around in some forms a decade after its release. As well as user and application monitoring, admins utilize Netflow for network planning, application reporting and profiling, security analysis, and usage-based reporting and billing.

cisco netflow router cache

Broadly, a flow is a group of packets part of the same conversation between two endpoints in a network. More technically, a single flow is defined by its 5-tuple, a collection of five data points that include:

  • Source and destination IPs addresses
  • Source and destination ports
  • The protocol

As you’d expect, the Cisco-developed protocol is supported by a number of CISCO networking devices. The company’s IOS-XR routers use a software implementation running on line card CPU, while the IOS line runs software on route processor. Meanwhile, Catalyst and Nexus switches have a dedicated hardware TCAM implementation, generally supporting more flows.

Netflow History, RFC, Netflow Vendor Variants

Free Webinar - Dealing with Remote VPN Challenges, Performance, Security & Monitoring

Posted in OpManager - Network Monitoring & Management

With a lot of enterprises switching to a work-from-home model, it is critical for admins to have a strategy in place to avoid poor performance and ensure secure access. This webinar will help you understand how you can effectively manage the security and performance of various components of your IT infrastructure even while working remotely.

Click here to register for this Free Webinar

manage engine webinar - the new normal remote workforce

Topics covered:

  • Why its critical to keep tabs on the availability and performance of servers and networks in your data center.
  • Effective ways to address and resolve real-time VPN monitoring challenges.
  • How to analyze and correlate network statistics to manage your networks better.
  • Threat factors IT admin need to be aware in order to ensure smooth transition to the new routine.
  • The need for application performance monitoring at the end-user level.

How to Enable or Disable SSH on VMware ESXi via Web GUI, vSphere Web GUI (vCenter), vSphere Client and Shell Console

Posted in Virtualization & VM Backup

SSH access to VMware’s ESXi server is by disabled by default however there are many reasons where SSH might be required. VMware and System administrators often find the need to perform advanced administrative tasks that require SSH access to the ESXi host. For example, deleting or reloading a VM with an Invalid Status can only be performed via SSH.

In this article, we’ll show you how to enable SSH on your ESXi host with just a few simple steps. This task can be achieved via the ESXi Web GUI, vSphere Web GUI (vCenter) vSphere client or ESXi console. We’ll cover all three methods.

Execution Time: 5 minutes

Security Tip: If your ESXi host management IP is not protected or isolated from the rest of the network, it is advisable to enable SSH on an as-needed basis.

Enabling and Disabling SSH Console on VMware ESXi via Web GUI

Log into your ESXi server and select the host from the Navigator window. Next, go to Action > Services and select the Enable Secure Shell (SSH) menu option:

vmware esxi enable ssh

This will immediately enable SSH. To disable SSH, repeat the same steps. You’ll notice that the Disable Secure Shell (SSH) option is now available:

vmware esxi disable ssh

Enabling and Disabling SSH on VMware via vSphere Web GUI Client (vCenter)

For those with a VMware vCenter environment, you can enable SSH for each ESXi host by selecting the host and then going to Manage > Settings > Security Profile > Edit.  In the pop-up window, scroll down to SSH Server and tick it. Optionally enter the IP address or network(s) you require to have SSH access to the host:

vmware esxi enable ssh vsphere web gui

Enabling and Disabling SSH on VMware ESXi via vSphere Client


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