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> vSphere HA indeed restarts the VM on a different host with its storage, network, etc. intact. This is so trivial that EC2 didn't offer it for years. How ofte

> vSphere HA indeed restarts the VM on a different host with its storage, network, etc. intact. This is so trivial that EC2 didn't offer it for years. How often is your hardware fucked up enough that you need to move to another machine? Honestly, if that happens often, there is something wrong with your hardware or your hardware provider or something. On a 900-servers fleet on AWS, yeah, sometimes it would warn me that "the server needs to be retired" or whatever. Then I stop the server, then start it. Sure, inconvenient, but happens maybe... once a month? In fact, the frequency is decreasing so maybe once every two months? > vSphere FT replicates a VM while it runs so that it doesn't even notice the failure of one of the underlying servers. That would be great, right? You paid some $ to VMWare and now your servers never go down? Excuse me but, that did not happen.

wmf 10y ago
Enterprise data centers are probably much less reliable than AWS. My take on HA & DR in general is that it's the kind of thing that you might use once in your career but it's probably worth it since it saves you from being fired.
- carterehsmith 10y ago
  I have to agree with that. Yeah, where I work, we spend a huge amount of time making sure that we are ready for something.. that may never happen. Makes you think. Thanks.
parasubvert 10y ago
"How often is your hardware fucked up enough that you need to move to another machine?" VMware HA runs quite a bit IME for a variety of reasons (network failure, storage issues, etc). "The network is reliable" is a classic fallacy of distributed computing. More often used is Vmotion and DRS which transparently moves VMs around physical hosts at runtime with no downtime and very minimal performance hit . Servers, switches, and fabrics need maintenance, firmware upgrades, hypervisor OS patches, etc. in most data centers. "That would be great, right? You paid some $ to VMWare and now your servers never go down? Excuse me but, that did not happen." VMware FT is used in almost every major company on the planet that runs virtualized database instances that can't go down. It is serious technology. AWS has mopped up the IT industry to date, and this is them going hard after Microsoft which is making inroads.

wmf 10y ago

Enterprise data centers are probably much less reliable than AWS. My take on HA & DR in general is that it's the kind of thing that you might use once in your career but it's probably worth it since it saves you from being fired.

carterehsmith 10y ago
I have to agree with that. Yeah, where I work, we spend a huge amount of time making sure that we are ready for something.. that may never happen. Makes you think. Thanks.

parasubvert 10y ago

"How often is your hardware fucked up enough that you need to move to another machine?" VMware HA runs quite a bit IME for a variety of reasons (network failure, storage issues, etc). "The network is reliable" is a classic fallacy of distributed computing. More often used is Vmotion and DRS which transparently moves VMs around physical hosts at runtime with no downtime and very minimal performance hit . Servers, switches, and fabrics need maintenance, firmware upgrades, hypervisor OS patches, etc. in most data centers. "That would be great, right? You paid some $ to VMWare and now your servers never go down? Excuse me but, that did not happen." VMware FT is used in almost every major company on the planet that runs virtualized database instances that can't go down. It is serious technology. AWS has mopped up the IT industry to date, and this is them going hard after Microsoft which is making inroads.