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When the Power Goes Out At Google
1sockchuck writes "What happens when the power goes out in one of Google's mighty data centers? The company has issued an incident report on a Feb. 24 outage for Google App Engine, which went offline when an entire data center lost power. The post-mortem outlines what went wrong and why, lessons learned and steps taken, which include additional training and documentation for staff and new datastore configurations for App Engine. Google is earning strong reviews for its openness, which is being hailed as an excellent model for industry outage reports. At the other end of the spectrum is Australian host Datacom, where executives are denying that a Melbourne data center experienced water damage during weekend flooding, forcing tech media to document the outage via photos, user stories and emails from the NOC."
Google was open. What exactly is the issue?
It gets really quite.
aren't there any people in the data center to tell them that yes there has been a power outage, so and so machines are affected, etc? sounds like all they have is remote monitoring and if something happens than someone has to drive to the location to see what's wrong
My lifestream was interrupted and I didn't even notice! (see http://tech.slashdot.org/story/10/03/08/0024205/Time-To-Take-the-Internet-Seriously for reference)
Flexible bare-metal recovery for Linux/UNIX
Jack must've forgotten to enter the code...
I thought that contracts required Google to disclose the cause and time of their downtime, and this disclosure is part of that.
Right now though, Google is making Microsoft look like they have better uptime for SaaS.
The price is always right if someone else is paying.
I pity EvilMuppet. Guy is a tool. There are contractual agreements that are in place to prevent pictures, aka the "rules" but when the data center blatantly LIES they are breaking the trust and violating the agreement. Case Law exists where contracts can be violated when one accuses the other of violating said contract.
That's what happened. The data center was lying about what happened to avoid responsibility for the equipment it was being paid to host. Pictures were taken and are being used to prove the company did violate the trust of the contract.
You can argue the semantics and legality of it but if this goes to court the pictures will be admissible and the data center will lose.
Obviously if the power goes out, and the service goes offline, then it WASN'T a cloud. If it's a cloud, it can't go down. If it goes down, it wasn't a cloud.
What's there to get?
Glen Beck, is that you!?
...but it was stored on Google Docs.
Even a cloud isn't effective if all the nodes go down, it's not magic.
A new option for higher availability using synchronous replication for reads and writes, at the cost of significantly higher latency
Anyone know some numbers around what "significantly higher latency" means? The current performance looks to be about 200ms on average. Assuming this higher availability model doesn't commit a DB transaction until it's written to two separate datacenters, is this around 300 - 400ms for each put to the datastore?
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
UPS's and backup generators? or some other onsite emergeancy power? (wind turbine, batteries, bunch of illegals on treadmills etc
App Engine must be Googles absolutely most poorly run project. It has been suffering from outages almost weekly (the status page doesn't tell the whole truth unfortunately), unexplainable performance degradations, data corruption (!!!), stale indexes and random weirdness for as long as it has been run. I am one of those who tried for a really long time to make it work, but had to give up despite it being Google and despite all the really cool technology in it. I pity the fool who pays money for that.
The engineers who work with it are really helpful and approachable both on mailing lists and irc, and the documentation is excellent. But it doesn't help when the infrastructure around it is so flaky.
Football Odds
This should be standard practice... It's like the good bits of ISO9001 with a bit more openness. When done right, ISO9001 is a good model to follow.
i don't run a data center, but manage systems that rely on the data center 18 hrs/day 6 days/week. we pass upwards of $300m through my systems. I've yet to get a satisfactory answer as to exactly what would happen if - say - a water line breaks and floods all the electrical (including the dual redundant UPS systems) in the data center.
The Kai's Semi-Updated Website Thingy
Whoosh.
OMFG! There's swinging at an outside pitch and there's try to hit one that was thrown in the fuckin' stands!!
I scream. You scream. I assume that means we're both acquainted with the problem. We proceed.
How did I end up in this article? Ah!!!
I scream. You scream. I assume that means we're both acquainted with the problem. We proceed.
Epic fail.
Any data center worth it's weight in dirt, must have UPS devices sufficient to power all servers plus all network and infrastructure equipment, as well as the HVAC systems too, for a minimum of at least 2 full hours on batteries, in case the backup generators have difficulty in getting started up and online.
Any data center without both adequate battery-UPS systems plus diesel (or natural gas or propane powered) generators is a rinky-dink, mickey-mouse amateur operation.
Sounds more like fog to me.
Davo -- Free speech, free software, AND free beer.
...a fairy dies.
Of COURSE there are people onsite. Most likely they have anywhere from a dozen to a hundred people onsite. But what's that going to do for you in the case of a large-scale problem?
The otherwise top rated 365 Main facility in San Francisco went down a few years ago. They had all the shizz, multipoint redundant power, multiple data feeds, earthquake-resistant building, the works. Yet, their equipment wasn't well equipped to handle what actually took them down - a recurring brown-out. It confused their equipment, which failed to "see" the situation as one requiring emergency power, causing the whole building to go dark.
So there you are, with perhaps 25 staff a 4-story building with tens of thousands of servers, the power is out, nobody can figure out why, and the phone lines are so loaded it's worthless. Even when the power comes back on, it's not like you are going to get "hot hands" in anything less than a week!
Hey, even with all the best planning, disasters like this DO happen! I had to spend 2 wracking days driving to S.F. (several hours drive) to witness a disaster zone. HUNDREDS of techs just like myself carefully nursing their servers back to health, running disk checks, talking in tense tones on cell phones, etc.
But what pissed me off (and why I don't host with them anymore) was the overly terse statement that was obviously carefully reviewed to make it damned hard to sue them. Was I ever going to sue them? Probably not, maybe just ask for a break on that month's hosting or something. I mean, I just want the damned stuff to work, and I appreciate that even in the best of situations, things *can* go wrong.
So now I host with Herakles data center which is just as nice as the S.F. facility, except that it's closer, and it's even noticably cheaper. Redundant power, redundant network feeds, just like 365 main. (Better: they had redundancy all the way into my cage, 365 Main just had redundancy to the cage's main power feed)
And, after a year or two of hosting with Herakles, they had a "brown-out" situation, where one of their main Cisco routers went partially dark, working well enough that their redundant router didn't kick in right away, leaving some routes up and others down while they tried to figure out what was going on.
When all was said and done, they simply sent out a statement of "Here's what happened, it violates some of your TOS agreements, and here's a claim form". It was so nice, and so open, that out of sheer goodwill, I didn't bother to fill out a claim form, and can't praise them highly enough!
I have no problem with your religion until you decide it's reason to deprive others of the truth.
try hiring some staff with telco experiance instead of kids with a perfect GPA scores from stanford and design the fraking thing better !
I think it would do them good, considering the recent downtime with Assassin's Creed 2. Has anyone seen any info on that outage?
Keith Olbermann, is that you!?
Fixed that for you
Google is lucky they have a second, third, n number of datacenters to failover to in the first place. You might be surprised how many large companies still rely on truck-shipped tapes or other "cold" disaster recovery methods even for their most critical business data. If you had to restore your systems via tape, would your company still be alive by the time you came back up? Or would the negative publicity from the event lead to a slow and timely death? Although this was an eye-opening experience for Google, it should be even moreso for companies who haven't had to experience this type of an event. Unfortunately in my experience many companies (Google included) will not change disaster recovery policies (or many other IT policies for that matter) until a significant event has occurred. The question is, should you bet your business and be reactive, or protect your business and be proactive? In Google's case, they were able to be reactive and will come out alright. Many others probably wouldn't be so lucky. All-in-all I believe this will be a great learning experience for Google, and as a side-effect will hopefully direct more people to looking at cloud technology to protect their business from outages.
Power failures are expected, what you can do is have plans for when they occur - batteries, generators, service migration to other sites, etc, etc
Too small scale, too complex, too much human intervention and too unreliable. Minimum of 2 datacenters on opposite sides of the world and you only send half the traffic to each. When the first vanishes the second picks up the traffic. The exact mechanism depends on the level of service you want to provide.
Deleted
Don't have all your shit in one data center, maybe? I'd have thought that one would be pretty fundamental. Of course, knowing Google they're going to decide that what they really need is power generation right on site, then they'll just pop off and invent nuclear fusion before lunch.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Did you ever actually see a big flood? Freaking awesome power, like a fleet of bulldozers. Smashes stuff, rips houses off foundations, knocks huge trees over, will tumble multiple ton boulders ahead of it, etc. Just depends on how big the flood is. We had one late last year here, six inches of rain in a couple of hours, just tore stuff up all over. The "building" that can withstand a flood of significant size exists, it is called a submarine. Most buildings of the normal kind just aren't designed to deal with anything that destructive. Some can resist minor floods, but not too many.
We decided to move three of our divisions into one facility, those included to business facing units and the I.T. division.
I was charged with laying out the design for data, telecom and electrical for the project. Also had engineering of our little NOC.
Nice setup - redundant power in the I.T. division, nice big APC UPS for the entire room, had it's own 480V power drop, dual HVAC units, a natural gas fired generator. It's nice to have the money to do this.
Since we were a state agency we had to use state DNS services. And one day the city had a massive power outage. We were up and running happy as a clam but we found the Achilles heel in all our plans. Without DNS we couldn't get in or out. I had floated the idea of maintaining our own DNS server but nobody wanted to hear that. We had the decent network connection, and the redundant power (Yes, we even placed a UPS/Generator backed up outlet in the MDF for Cox's Marconi router) so why the hell not replicate the state DNS services?
Let that be a lesson. We tried to plan for all contingencies and we completely missed our dependence on an outside state agency. Of course since a river runs right behind we also raised the NOC floor by about a foot.
Wow, that cloud's on the move!
Obviously if the power goes out, and the service goes offline, then it WASN'T a cloud. If it's a cloud, it can't go down. If it goes down, it wasn't a cloud.
The cloud got too big and it rained.
$Political_Pundit_I_Disagree_With, is that you!?
Fixed that for you
No, I think I got it right this time.
Posts not to be taken literally. Almost everything is sarcasm.
I have seen data centers crash. I do not think it is likely in this case but twice I have seen issues with the UPS system take a datacenter down
Once a battery in the UPS system blew up and sprayed acid on the wall as it crashed. Once a component inside died.
I have also seen them go down due to too much stuff plugged in not really a ups issue.
Funny thing is in the seven years I was working there, I never saw the mains drop. It could have happened for a few seconds but they came back up before I was paged.
Usually our data center was affected by HVAC issues.
I turn on my TV or go outside to return to a normal life.
I read the post-mortem and I think they completely missed the mark. Power failed to some machines. They only noticed because "...traffic has problems..." They should have been monitoring the power to detect this situation. They didn't say whether they have the data center power supply on a UPS or not. If it was, it was dying and no one noticed. If they had been monitoring the power they might have avoided the whole mess.
Repeat to yourself: "All is well, All is well, All is well" and everything will be exactly like you wish it to be.
Note originators of response model are not responsible for anyone being taken away to a psychiatric facility because of a belief response model user is psychotic
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They'll come out with it when Apple releases iFusion...
The local power utility accidentally tripped the only bus supplying the 30MW of power to the data center.
Google's data center lost all power for 8 seconds before the generators, and not all of them, came online.
The UPS system failed completely.
This facility is about 2 years old in SC.