Hp storage D2d4324 nfs slow xenserver
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
If you setup xenserver with ha you need a storage repository for all 3 nodes to share the vm so if one of the machines drops off the next machine in the cluster will pick up where the machine that dropped off using the shared storage repository
that's correct, but that doesn't imply EXTERNAL storage, only that you have to make their internal storage shared. Using external storage like this just adds a new point of failure that isn't addressed at all. So you aren't making anything HA, you are just shifting (and increasing) the risk by adding more risk and reducing none. You are thinking of HA as only applying to one basically inconsequential piece of the system and missing the reliability of the system as a whole.
https://www.mangolassi.it/topic/8821/risk-3-2-1-stock-inverted-pyramid-design/
https://www.mangolassi.it/topic/8743/risk-single-server-versus-the-smallest-inverted-pyramid-design/
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So then how do I create a cluster ? With high availability with no shared storage
I didn't say no SHARED storage... no EXTERNAL storage. The two are very different things.
With clusters of three or fewer nodes, local disks are the only option... period. And for a dozen or fewer hosts they are the only common option. External storage is only viable at very large scale and has but one purpose... cost savings at massive scale. It is never for features or availability... external storage works against those things. Only scale would ever make external storage even a discussion point.
http://www.smbitjournal.com/2013/07/replicated-local-storage/
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For XenServer, which has high availability shared storage built in out of the box, you literally need nothing. HA-Lizard is a script that sets things up for you. You can use Starwind for larger scale. HP VSA will work as well. You can use Gluster or CEPH, too.
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So then how do I create a cluster ? With high availability with no shared storage
@scottalanmiller said in Hp storage D2d4324 nfs slow xenserver:
For XenServer, which has high availability shared storage built in out of the box, you literally need nothing. HA-Lizard is a script that sets things up for you. You can use Starwind for larger scale. HP VSA will work as well. You can use Gluster or CEPH, too.
XenServer and HALizard is only for 2-node setups IIRC. XenServer by default is capable of setting up a 3-node (or more) HA pool that doesn't require anything else.
XenServer (and team) specifically design XenServer to be configured standalone for 3-host or more for true HA.
If you're going to use HALizard you'd only run 2 host, and configure them in a pool. Run the script on each server, create the virtual iSCSI between the hosts and let it sync.
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@DustinB3403 said in Hp storage D2d4324 nfs slow xenserver:
@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So then how do I create a cluster ? With high availability with no shared storage
@scottalanmiller said in Hp storage D2d4324 nfs slow xenserver:
For XenServer, which has high availability shared storage built in out of the box, you literally need nothing. HA-Lizard is a script that sets things up for you. You can use Starwind for larger scale. HP VSA will work as well. You can use Gluster or CEPH, too.
XenServer and HALizard is only for 2-node setups IIRC. XenServer by default is capable of setting up a 3-node (or more) HA pool that doesn't require anything else.
XenServer (and team) specifically design XenServer to be configured standalone for 3-host or more for true HA.
If you're going to use HALizard you'd only run 2 host, and configure them in a pool. Run the script on each server, create the virtual iSCSI between the hosts and let it sync.
Yes, for three hosts or more you need someone like Starwind or Gluster.
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So basically what your telling me.. For what I am trying to do I am shooting myself in the foot. FYI I am trying to build my own webhosting network. I have fiber and need to setup the servers properly
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So basically what your telling me.. For what I am trying to do I am shooting myself in the foot. FYI I am trying to build my own webhosting network. I have fiber and need to setup the servers properly
Don't feel to bad - this is definitely a difficult thing to understand. it just happens to be one of Scott's fortes. Now the rest of us understand it and pass it along as well.
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@scottalanmiller how would I set up what I am trying to achieve. I want to have cpanel servers with fail over
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So basically what your telling me.. For what I am trying to do I am shooting myself in the foot.
Correct, but don't feel bad, every sales person in the world pushes this exact design so you hear it so often that it sounds plausible. I have an article on that, too.
http://www.smbitjournal.com/2016/06/the-emperors-new-storage/
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
@scottalanmiller how would I set up what I am trying to achieve. I want to have cpanel servers with fail over
Let's start with scale. How much server capacity do you need if capacity alone is the factor at hand (does one server handle enough capacity for your needs?) Don't worry about numbers for failover or anything like that... we will tackle that next. How much storage, RAM and rough CPU do you need to get the job done today? And how much do you anticipate in 6 months and two years?
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@scottalanmiller said in Hp storage D2d4324 nfs slow xenserver:
For XenServer, which has high availability shared storage built in out of the box, you literally need nothing. HA-Lizard is a script that sets things up for you. You can use Starwind for larger scale. HP VSA will work as well. You can use Gluster or CEPH, too.
+++
Also it's a very common misconception in a hyperconverged scenario ALL the nodes should participate in the storage providing. It's not! There may be storage only nodes, compute only and hybrid. In a very different configurations. Pretty much all the HCI vendors can do that, especially if they support common uplinks (NFS, SMB3 etc).
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So in your expect opinion what would be the proper setup for what I am trying to achieve. I am trying to create a fail over cluster running websevers using cpanel.
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So in your expect opinion what would be the proper setup for what I am trying to achieve. I am trying to create a fail over cluster running websevers using cpanel.
What you're running as a VM on the hypervisor doesn't effect the design of the hypervisor and fail-over capabilities. (generally)
If you only have the two host, you'll want to configure them in a HA pool.
Then the VM's would be able to live migrate without downtime between the two hosts.
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
So in your expect opinion what would be the proper setup for what I am trying to achieve. I am trying to create a fail over cluster running websevers using cpanel.
Well, that's a little complex so let's delve into it. What processes do we need to protect? In most cases we do high availability at the application layer, not at the platform layer. This is where you get the best reliability. What web servers are you running, what kind of applications are on them and what dependencies (like databases) do they have?
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@DustinB3403 said in Hp storage D2d4324 nfs slow xenserver:
What you're running as a VM on the hypervisor doesn't effect the design of the hypervisor and fail-over capabilities. (generally)
osts.Sort of..... but only because more than 50% of the time what you run tells you that HA has no function at the platform level at all. Web servers, file servers, active directory and such you generally let do their own HA and you avoid hypervisor HA because it interferes with the HA that is already there.
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We are running wordpress websites, nothing crazy. using mysql. we are using xenserver. and thats basically it .
The server specs are
hp dl360 g5 dual quad core I believe 32 or 64 gig of ram.
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
We are running wordpress websites, nothing crazy. using mysql. we are using xenserver. and thats basically it .
The server specs are
hp dl360 g5 dual quad core I believe 32 or 64 gig of ram.
MySQL / MariaDB has its own means of doing HA that is more powerful than what the hypervisor can do (HV can only do crash consistent whereas the database itself can do true HA and Fault Tolerance with zero data loss) and making Wordpress highly reliable is just a matter of load balancing the traffic.
So in a case like this, I would not have any HA at any level except for the applications. Just have two (or more) host nodes with zero shared infrastructure (no HA at any level, no shared storage, etc.) and let the applications (Apache and MySQL) do their jobs.
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SO are you saying... us ha lizard or something like that?
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@mroth911 said in Hp storage D2d4324 nfs slow xenserver:
SO are you saying... us ha lizard or something like that?
No he's not.
If you need to create HA for Active Directory, you buy two servers and install a ADDS server on each. The HA is provided at the software level of Windows, not at the hardware level or hypervisor level.
Scott is telling you that Apache and MySQL can do exactly that - skip the hypervisor HA and only use application HA. You'll also probably want to buy a load balancer to sit infront of these two servers as well.
