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Let’s say you want  high availability at the NIC level  and failover capacity to the CVM and user VMs. We recommend using  balance-slb to take advantage of all adapters. Balance-tcp is a load balancing method that increases host and VM bandwidth utilization beyond a single 10 Gb adapter by balancing each VM NIC TCP session on a different adapter. Also used when network switches require LACP negotiation."   Advantages of Bond Mode for balance-slb Balance-slb bond mode in OVS (Open vSwitch) takes advantage of all the links. Rebalance VM traffic from the interface that is used extensively to less use

On your Nutanix and vSphere cluster you may have recently seen this alert stating “Storage Containers are not mounted on all nodes”. This may have started showing up after some cluster modifications or maintenance, or could have appeared after some recent upgrades.  You’re probably wanting to know, what is this alert for? How big of a problem is it and what do we need to do to fix it? I’d like to answer those questions for you. This alert is generated through a recurring NCC check “Storage Container Mount Configuration”. First off it’s useful to know that the main purpose of this check is to validate the configuration of  a Metro Availability pair of Nutanix/ESXi clusters. That’s why this check is categorized under the data protection checks. The command to run this check from the CVM CLI is “ncc health_checks data_protection_checks protection_domain_checks storage_container_mount_check”. As for the impact of the problem being reported I’d have to say it’s condi

Hi,Our metro cluster is running AOS5.10.8.1 (since yesterday’s update from AOS 5.10.8) on x8 NX-8035-G6. During an LCM update for bios and HDD, a node failed due to a bad DIMM. The node pair were eventually evicted from the meta data ring at which point support were supplying a replacement DIMM. After a lot of coaxing both nodes were back in the cluster and hosting vSphere6.5 without any apparent issue, however, since the outage we are being warned in PC\PE and NCC that the active and standby PDs are not mounted on all nodes, even after manually ensuring that the containers are available and connected correctly. Support have advised that this is a known NCC error and just wondered if anyone else in the community has experienced this issue? Thanks in advance

 There may come a time when you must expand your cluster storage capacity since you predict more data will be added to the cluster in the near future.Also, you are already short of space and cannot gain any more space by deleting the old snapshots and removing VM not needed any more, etc.In that situation, assuming you have empty slots in your hardware chassis and depending on the type of the drive you are adding you will need to follow the instruction in your nutanix portal document titled “Adding a Drive”.If you do not have any more disk slot on your hardware to, you may have to add a new node to your cluster altogether, so it can expand the capacity of your cluster. This has the benefit of adding memory and cpu resourc

Hi, I am trying to create a VM using the v3 API and have a question about creating the vdisks. I can specify the disk details (size, type, etc.) in the create VM call, but don't seem to be able to specify the storage container to use. Is this correct?  The only work around that I've found is to use the v1 API to create the vdisk, grab its UUID, and use that in the v3 call to create the VM. I can't see a call to create a vdisk in either v2 or v3. Darren.

First of all, let’s take a look at what all-flash and hybrid nodes mean. All-flash:- Nodes containing only SSD drives Hybrid nodes:- Nodes containing both HDD and SSD drives.   Is it possible to have both kinds of nodes within the same cluster? – Provided that the two conditions below are met, it is: The AOS version must be 5.1 or later. The minimum number of each node type (all-flash/hybrid) must be equal to the cluster redundancy factor. For example, clusters with a redundancy factor of 2 must have a minimum of 2 hybrid and 2 all-flash nodes.   To check for any issues with mixing t

The Unified Extensible Firmware Interface (UEFI) is a specification that defines a software interface between an operating system and platform firmware. UEFI replaces the legacy Basic Input/Output System (BIOS) firmware interface originally present in all IBM PC-compatible personal computers,with most UEFI firmware implementations providing support for legacy BIOS services. UEFI can support remote diagnostics and repair of computers, even with no operating system installed.Advantages :The interface defined by the EFI specification includes data tables that contain platform information, and boot and runtime services that are available to the OS loader and OS. UEFI firmware provides several technical advantages over a traditional BIOS system:

You might receive an error of low free block count in your NCC report due to failed check sata_dom_fwv_check.   This plugin checks the SATA DOM SMART data and shows if anything is off from the expected result.   To free up blocks in the SATA DOM, we have a procedure called, “Trim Operation” which is effective and really quick. The trim operation consists of running a script called trim_satadom.sh which can be downloaded from the link provided in the below mentioned doc.   To get to know more about the NCC check and to see how the Trim operation works, take a look at-

Oops, did you by mistake created a VM on SATA DOM? What will happen if a VM is intentionally created on SATA DOM?   For starters, it is not recommended to run VMs on the SATA DOM, as this accelerates the degradation. If by mistake you did it, how will you know?   The NCC health check sata_dom_uvm_check verifies if there are any VMs running on the SATA DOM, and reports a FAIL status if the check detects any VMs running on the SATA DOM.   Now as the check suggests that there is a VM running on SATA DOM, the only solution would be to take it out of the

IPMI version 2.0 is susceptible to exploitation that allows an attacker to obtain password hash information.   The vulnerability scan on the environment can give the below sample output:-  Synopsis :The remote host supports IPMI version 2.0.Description :The remote host supports IPMI v2.0. The Intelligent Platform Management Interface (IPMI) protocol is affected by an information disclosure vulnerability due to the support of RMCP+ Authenticated Key Exchange Protocol (RAKP) authentication. A remote attacker can obtain password hash information for valid user accounts via the HMAC from a RAKP message 2 response from a BMC.   To know the IPMI version on the host, login into the host, run the command

Is it possible to share a disk between two or more Virtual Machines? Can we use the disk on the two VMs at the same time, for reading and writing?   The answer is Yes and No respectively.   Yes, Nutanix supports shared disk via Volume Group on AHV. This is supported on clustering solutions (Cluster at guest OS level) like My SQL etc.   You can use the disk on the two VMs at the same time for reading. However, two VMs writing at the same time is not allowed.    In a clustering solution, the master VM will write to the disk and all the other VMs in the cluster can read from the disk.    Take a look at the guide to

Let’s say you want to add a new node with a newer processor class than the existing nodes in the cluster. In this case you must enable EVC (Enhanced vMotion Compatibility) feature.   What is EVC?   EVC stands for Enhanced vMotion Compatibility which is a vCenter Server cluster-centric feature allowing virtual machines to vMotion or migrate across ESXi hosts equipped with dissimilar processors in the same cluster. VMware EVC Mode works by masking unsupported processor features thus presenting a homogeneous processor front to all the virtual machines in a cluster. This means that a VM can vMotion to any ESXi host in a cluster irrespective of the host’s micro-architecture examples of which include Intel’s Sandy Bridge and Haswell. One caveat to remember is that all the processor(s) must be from a single vendor i.e. eit

Are you wondering which alerts generate a support case with Nutanix Support and whom Nutanix contacts when a case is generated? There is a particular subset of alerts that have been identified as being important, so action can be taken on them. These alerts are called Alert cases. When the cluster is under a current support contract, alert cases are generated. Alert cases are handled by Nutanix Support, who reach out to the primary Support Contact (also referred to as the break/fix contact) associated with the node or cluster in question. For customers with a third-party providing front-line support, it is normal to have a representative from that company listed as the primary Support Contact.

On a Nutanix cluster running VMware vSphere, you may be seeing this alert while there is no other sign of issue: Warning : Some storage containers have a high number of NFS files Impact          : High number of NFS files may cause vpxa services on esxi hosts to restart. Cause           : Number of files for respective storage containers has increased beyond 20K. This is expected with large VDI setups. Resolution      : Reduce the number of files if you observe vpxa instability. Why do we see this alert? What needs to be done about it? As is noted on the relevant KB article this alert is set to be deprecated in an upcoming release of NCC. As suggested by the Impact and Resolu

Below are the top knowledge base articles for the month of February 2020 KB 4116 - Alert - A1187, A1188 - ECCErrorsLast1Day, ECCErrorsLast10Days KB 4141 - Alert - A1046 - PowerSupplyDown KB 7503 - G6, G7 platforms with BIOS 41.002 and higher - DIMM Error handling and replacement policy KB 1540 - What to do when /home partition or /home/nutanix directory is full KB 1113 - HDD/SSD Troubleshooting

Below are new knowledge base articles published on the week of February 23-29, 2020. KB 8900 - Prism Central Alert Manager and Cassandra Monitor services crashing, NCC health checks failing for same. KB 8909 - [Karbon] Airgap (dark site) FAQ and Troubleshooting Guide KB 8956 - AHV | How to get a list of virtual machines that were restarted due to an HA event KB 8976 - Nutanix Files Share might encounter mapping issue to macOS KB 8980 - VMs delet

 Is there a way to create isolated networks within the nutanix cluster that would allow communication only for the VMs that has a NIC connected to that network? Find attached an example of what I mean if we were talking about ESXi Thanks in advance!

Can anyone let me know which steps are being involved when I expand Hyper-V cluster by using Prism? I have a Hyper-V cluster that being mixed by some AHV storage nodes and looks like I cannot use the Prism cluster expansion feature to add more nodes...

Dear All Is it mandatory to replace the node in a cluster with the same hardware? Can we replace it with a higher configuration(CPU)

If you have a Nutanix cluster on VMware vSphere which has been through some hypervisor upgrades, your CVM’s virtual hardware version may be a bit out of date. The main requirement from the Nutanix perspective is that CVM virtual hardware versions should be the same across the AOS cluster, and this is checked by NCC. Still, since newer virtual hardware versions include security updates and sometimes feature updates or improvements from VMware you may want to bring this up to date. If you have an AOS upgrade pending, completing that upgrade would be the easiest route to solution. If you don’t have any AOS upgrade needed, please note Nutanix does not recommend manually updating the VM hardware version for CVMs. The recommended metho

Lets say that you want to monitor or modify your cluster by utilizing some of our REST APIs.  To view Nutanix REST APIs, go to Prism > click on the username on the top right > REST API Explorer.  Automating the API calls can make your daily tasks easier and faster, it's a script that you write once and you can use it via bots on chat platforms like Slack and Google Hangouts.  For example, if you have multiple clusters and you wish to see the alerts on all of them, you have the option to automate a script that sends you the alerts by simply writing "<cluster name> alerts" as opposed to logging in to each cluster and inserting the credentials every time.  Here is my example snippet of a server-side automation with Node.js, the call is to show the alerts on a cluster named Prolix where you can send a basic Auth credentials to pass the login page, the parsed result will be printed in the console.

You might receive an alert stating that “IP x.x.x.x is authenticating to the REST API with the admin user.” The cause of this alert is that an external client is configured to authenticate to REST API with the admin user.   The admin user will be disabled in a forthcoming release. REST API calls from the admin user will stop working. The resolution is to authenticate to the REST API with a different user that has administrative privileges.   To resolve the warning, create another user as per the below procedure. This user can authenticate to the REST API without an alert being raised.  

There can be many scenarios like PSU troubleshooting or upgrades where we might want to know the current BMC and BIOS version in the cluster. Let’s say for a tracking/planning sheet of firmware upgrades or sometimes its asked from the Nutanix support for an open case you have.   There are two ways to get this information. Using IPMI or cli to get the BIOS and BMC versions on individual nodes. Using NCC to determine the model, BIOS and BMC version for all nodes.   To know in detail about the above methods take a look at https://portal.nutanix.com/#/page/kbs/d

Could some one help me to understand how to calculate CVM overheads? I mean witout using the Sizer. I'm prety sure that some time before I have seen something about that in the documentation but now is removed. Nutanix bible sows some infor Drive Breakdown section but I'm not sure that it is up to date. So my question is how I can calculate overheads for the below: SSD: Nutanix Home Ext4 Formatting Genesis Cassandra OpLog Content Cache HDD Ext4 Formatting Genesis Curator

Running the checks "CVM using default password", HOST using default password", IPMI using default password", I always get green status even if the CVM, HOSTS and IPMI passwords are the default ones. Why?