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I would like to setup a free/custom solution to perform failover for VMware ESXi.

The setup is as follows:

2x Physical servers each with independent storage. For each physical server there are 2x Win2k8 Enterprise servers.

In the case a physical server completely fails, we want the other (for convenience sake we can assign it with a slave role) to resume operation.

For this to occur, we need to somehow do continuous replication of the virtual servers, and in the case of the primary server failing have it take over the IP, start the virtual machines and continue operation.

I am new to VMware ESXi myself, but I am trying to research alternative solutions to the expensive VMware licensing for failover.


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closed as off-topic by EEAA, Falcon Momot, gWaldo, Ladadadada, TheCleaner Sep 5 '13 at 20:14

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions seeking product, service, or learning material recommendations are off-topic because they tend to become obsolete quickly. Instead, describe your situation and the specific problem you're trying to solve." – EEAA, Falcon Momot, gWaldo, Ladadadada, TheCleaner
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Buy the proper licenses. High availability doesn't come cheap. You need a high quality SAN to ensure high availability anyways. The extra license for VMotion is a drop in the bucket compared to the price of the SAN. If you're really worried about licensing, you can use Hyper V which gives you failover at no additional cost. You still need a SAN for this to work and if you get a cheap SAN, you get low performance, low reliability, and it possibly won't work at all.

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You can get the full solution (not free) from VMWare with high availability, failover, etc...expensive. You also need the equipment (a shared storage SAN configuration between two identical servers).

You can rig up something using a SAN (you'll want shared storage anyway) and two identical ESXi servers so that if something failed, you could bring up another server fairly quickly. Not so automatic, though.

Last, you could look into assembling a couple of systems and mirroring the servers with something like DRBD to replicate the data volumes across dedicated IP connections; you'd not be using ESXi, though. You'd be using VMWare Server on Linux systems. I'm sure there are other ways to do it, but you'll be dedicating a lot of time and duct tape to get a home grown solution like that.

Personally, we don't need the 24/9 five nines uptime, so we are trying to get two servers, identically configured, with copies of the server VM's made periodically to a network storage device so that if a system fails we can copy over the VM and fire it back up within a few hours. We also have backups of some of the VM's within the VM using our backup software, so if push comes to shove we can create a "blank" VM and run a restore from the backup server.

If your business MUST have these VM's need to get the full ESX package, with support from VMWare. If not, feel free to cobble things together, or you can look into the high availability Linux project information for configuring things like DRBD and heartbeat and clustering and fencing and all the wonderful things to worry about when running high availability servers in a virtual world.

Good luck!

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With local disks and ESXi, there's no way to do realtime replication.

The system we have is two ESXi servers that use ghettoVCB to copy images of the VMs to a central NAS every night, so we can load them off there if needed. A simple script could check to see if one server was down, and boot up VMs on the other using this (check for ping, if not then something like vim-cmd vmsvc/power.on <id>

However, as Jason says, if you need this kind up uptime, you need proper ESX licenses, and a SAN between them.

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I'll echo what others are responding with, that proper high-availability isn't cheap and that if you're trying to cut corners with this, evidently HA isn't really important enough to your business. If it was, you'd be laying out the appropriate investment for the appropriate return.

If you're a small shop and need this on less than 3 ESXi hosts per site, investigate the VMWare Essentials pricing model. It's very cheap (relative to the regular socket licences), and vMotion, FT, DRS and HA are available within the scheme. There are also license-up options if your requirements grow in the future.

That said, you can still leverage your application/OS level clustering technologies inside VMs running on ESXi, as you would do with physical machines. I'd recommend you pursue clustering within the OS or apps to solve your problems.

You're reasonably unlikely to find a hypervisor-level solution to your problem with ESXi, because VMWare specifically requests that vendors do not ship solutions for the free version which conflict with the licensed versions of ESXi. Classic example - Veeam used to support the free ESXi in their backup tools. VMWare contacted them and requested that they stop doing this, as the vBackup APIs are only exposed once a host is licensed. Veeam complied, and ESXi free support isn't available in Veeam backup any more.

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Like Jason said, if you want failover you will need some SAN storage solution, and VMWare licensing is a small thing compared to that. Did you asked some VMWare partner for a quote of vSphere Essentials Plus? It's a bundle that includes licensing for 3 hosts (each with up to 2 six-core physical processors), vCenter for those 3 hosts, HA, AND vMotion, for just around U$2k.

If you want some "high availability" solution being really cheap, use XenServer or Hyper-V, and a machine running OpenFiler as an iSCSI storage target.

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I'd +1 this if you didn't recommend openfiler...first of all, it won't work with a Hyper V cluster (no iSCSI-3 support)...also, I wouldn't call it high availability if you're putting a single server as your single point of failure again...SANs usually have lots of redundancy in them, more than any server – Jason Berg Aug 31 '10 at 4:11

No its all free, just have 2 vm hosts, put your datastore on a NAS box, then have both vm hosts point to the network datastore.
Leave 1 server off, and if lets say vm host 1 fails, you just turn the other one on.

What's so hard about that ey? lol beats the $10,000+ licensing costs now doesn't it. You will oboviously need to backup or replicate your NAS as well and back that up often.

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That is a total hack, and doesn't provide the automated failover that would be necessary in any kind of enterprise environment. Props for creativity, but seriously? Spend the money on the VMWare licenses for the features you need, or use Hyper-V... – voretaq7 Sep 6 '13 at 19:11