Xen Server 6.5 + Xen Orchestra w. HA & SAN
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Are you sure that all of this makes sense in your environment? This is two orders of magnitude from where you have been in the past. It isn't normal to have an LA (low availability) environment and get by for a long time and suddenly leap to HA. Why not just go to standard availability? It's a full order of magnitude safer than where you have been in the past, almost zero effort (and no risk from that lack of effort... simple is your friend) and less than half the price of doing HA.
SA is the only clear win... tons safer, tons cheaper. HA is tons safer for sure, but costs more and doesn't make sense given what was deemed acceptable in the past.
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Looking to develop hardware costs and quotes for new equipment. Company wants to grow employee's to 500+ by year 2020. Need to have reliable servers hosting VM's
If the primary xenserver host fails.. then what? We have a day + of downtime waiting for server to come back online?
Looking to future proof so can be in production for next 5 years. I may not be here with company in next 5 years, so want to leave behind a good setup.
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@scottalanmiller said:
Are you sure that all of this makes sense in your environment? This is two orders of magnitude from where you have been in the past. It isn't normal to have an LA (low availability) environment and get by for a long time and suddenly leap to HA. Why not just go to standard availability? It's a full order of magnitude safer than where you have been in the past, almost zero effort (and no risk from that lack of effort... simple is your friend) and less than half the price of doing HA.
SA is the only clear win... tons safer, tons cheaper. HA is tons safer for sure, but costs more and doesn't make sense given what was deemed acceptable in the past.
also to mention, I've been hammering HA setup for awhile to management; for peace of mind and rest-easy at night. Yes, we've been getting along with low availability type setup for now. But as the resource usages increase; i feel the need for HA setup with dual nodes.
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@ntoxicator said:
Looking to develop hardware costs and quotes for new equipment. Company wants to grow employee's to 500+ by year 2020. Need to have reliable servers hosting VM's
That's fine. But that doesn't suggest HA at all.
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@ntoxicator said:
If the primary xenserver host fails.. then what? We have a day + of downtime waiting for server to come back online?
This is not how you discuss risk. This tells me that HA is not needed. This isn't how a "we need HA" discussion would start.
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@ntoxicator said:
Looking to future proof so can be in production for next 5 years. I may not be here with company in next 5 years, so want to leave behind a good setup.
This strongly says that HA is a bad idea as it requires a lot more skill, documentation, knowledge, etc.
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@ntoxicator said:
But as the resource usages increase; i feel the need for HA setup with dual nodes.
Resource utilization does not lead directly to needing higher availability. Wall St. firms don't need HA on billion dollar trading systems, why do you feel that moving to 500 users warrants in for you but hundreds of thousands of users does not warrant it for them?
That's not to say that HA can't be right for you, I'm saying that you aren't thinking about it in the way that you should if you were going to determine that HA was needed.
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@scottalanmiller said:
@ntoxicator said:
Looking to future proof so can be in production for next 5 years. I may not be here with company in next 5 years, so want to leave behind a good setup.
This strongly says that HA is a bad idea as it requires a lot more skill, documentation, knowledge, etc.
And if HA is determined to be needed, it needs to be an appliance, not a solution that they will be unable to support.
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Server planning for five years out is relatively risky. Not bad, but we know just about nothing about the future. And "the company wants to grow" should not lead us to spending today. A 200 person company buying hardware like they are a 500 person company is the hallmark of a company that is never going to get to 500. Projections like that are not things that IT acts on, that would lead to some dangerous stuff.
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Ok, why dont you come consult for us then? Explain why HA is not needed and list the negatives and upside.
I dont get why your so anti-HA?
So we get another single server, spec'd full of drives and hope that we dont have a hardware failure
What are chances of mobo dying on Dell R730? or integrated NIC card failing, etc? I suppose low percentage rate.
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CEO/CFO & management, will not purchase new hardware unless they're certain it'll last for 5+ years and handle the load of 500+ employee's by year 2020. All by company projections and their hiring needs/growth rate statistics.
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@ntoxicator said:
I dont get why your so anti-HA?
I "pro-good business decisions", if that sounds anti-HA, it is self explanatory.
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@ntoxicator said:
Ok, why dont you come consult for us then? Explain why HA is not needed and list the negatives and upside.
That's what I do for a living, I help CEOs and CFOs understand how finances play into IT and help steer companies away from exactly these kinds of problems. I specifically am the person who does this, that's my focus.
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For HA, two nodes.
It comes down to understanding the hardware and the MTBF? Understanding the common failures of said server/generation/caveats?
Understanding risk or percentage change as to an actual hardware failure which would result in a node going down, and the need for fail-over scenerio
I see those as logical talking points and reasoning when looking at HA and if its a need or not
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@ntoxicator said:
So we get another single server, spec'd full of drives and hope that we dont have a hardware failure
Well, that is WAY better than where you are today, right? It would...
- Save you a ton of money.
- Improve your reliability by a full order of magnitude.
- Be far easier to maintain.
- Not waste money that might be needed for growth.
- Allow you to get a decent support contract.
- Be easily able to be handed off to an MSP or your replacement someday.
- Not require that your shop develop and maintain indefinitely more skills than it otherwise needs.
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@ntoxicator said:
What are chances of mobo dying on Dell R730? or integrated NIC card failing, etc? I suppose low percentage rate.
Around five nines of reliability. On average these fail about once every 15 years. How much money are you willing to spend today to avoid a disaster that has almost no chance of happening during the life of your server?
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@ntoxicator said:
CEO/CFO & management, will not purchase new hardware unless they're certain it'll last for 5+ years and handle the load of 500+ employee's by year 2020. All by company projections and their hiring needs/growth rate statistics.
Then they are idiots. Sorry, that's as honest as I can be. For IT to say that is fine, IT people aren't financially trained. For a CEO and CFO to state something so financially juvenile and reckless means that you should be worried about their ability to run the company. I'm very serious. That's like high school level business mistake there. Even a college kid just taking early business classes should know far better than to think of ANY financial investment in terms other than "what is best for the business." They are getting emotional and emotional C levels drive companies in the ground.
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Oh talk to me about emotional responses..
It would be worth its own topic.
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@ntoxicator said:
For HA, two nodes.
It comes down to understanding the hardware and the MTBF? Understanding the common failures of said server/generation/caveats?
Understanding risk or percentage change as to an actual hardware failure which would result in a node going down, and the need for fail-over scenerio
I see those as logical talking points and reasoning when looking at HA and if its a need or not
Not really. Those are background noise.
All HA discussions, all... no exceptions, come down to two factors and two factors alone...
- How much money is lost from different downtime events.
- How much money can be spent to mitigate those events to what level.
That's it. That's the whole thing. You are currently skipping the first step entirely. Your CFO, even if it is his first day working in any business, should be all over that. Even a business intern from college should be all over the fact that the "risk" isn't being considered at all. Risk is measured in dollars and no one has thrown out a figure yet. So the very first thing you need to have this discussion... in fact the only thing that should trigger this discussion... is missing.
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@scottalanmiller said:
@ntoxicator said:
CEO/CFO & management, will not purchase new hardware unless they're certain it'll last for 5+ years and handle the load of 500+ employee's by year 2020. All by company projections and their hiring needs/growth rate statistics.
better than to think of ANY financial investment in terms other than "what is best for the business." They are getting emotional and emotional C levels drive companies in the ground.
I think you made a point here and the comment around "What is best for the business". They're trying to also operate on a cash basis... also building out a new 70,000 - 112,000 sq ft. facility to house all new employee's. to be built by end of 2017. I personally doubt their timeframe. I have my doubts
I've tried to explain my case and even a new single server approach (updated hardware & specs) to hold our VM resource needs... always gets brushed off. Happening for past year.
However, have recently asked I find pricing/quotes for equipment and see what other companies of 'our size' are doing and have success with.
