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Ask Slashdot: Little Boxes Around the Edge of the Data Center?
First time accepted submitter spaceyhackerlady writes "We're looking at some new development, and a big question mark is the little boxes around the edge of the data center — the NTP servers, the monitoring boxes, the stuff that supports and interfaces with the Big Iron that does the real work. The last time I visited a hosting farm I saw shelves of Mac Minis, but that was five years ago. What do people like now for their little support boxes?"
I make them with ticky tack.
Give me Classic Slashdot or give me death!
Call me old school, but Unix/Linux are multi-tasking. Why not just run multiple services on one OS directly on the metal?
"I don't know, therefore Aliens" Wafflebox1
I don't work in a data center. But I think you might want to look at an HP Proliant MicroServer.
Basically it is an AMD laptop chipset on a tiny motherboard in a cunningly designed compact enclosure. The SATA drives go into carriers that are easily swapped (but not hot-swappable). It's quiet and power-efficient. It supports ECC memory (max 8GB) and supports virtualization.
http://h10010.www1.hp.com/wwpc/us/en/sm/WF06b/15351-15351-4237916-4237918-4237917-4248009-5153252-5153253.html?dnr=1
Silent PC Review did a complete review of an older model (with a 1.3 GHz Turion instead of 1.5 GHz).
http://www.silentpcreview.com/HP_Proliant_MicroServer
SRP is $350, but Newegg has it for $320 (limit 5 per customer).
http://www.newegg.com/Product/Product.aspx?Item=N82E16859107052
Newegg also has 8GB of ECC RAM for about $55, so you can get one of these and max its RAM for under $400.
I just got one and haven't had time to really wring it out, but I did do the RAM upgrade. Despite the tiny enclosure, it wasn't too painful to work on it, and I was impressed by the design. The Turion dual-core processor has a passive heat sink on it, and the single large fan on the back pulls air through to cool everything. (There is also a tiny high-speed fan on the power supply.)
I'm going to use this as my personal mail server. It's cheap enough and small enough that I plan to have at least one put away as a hot spare; if the server dies, I'll power it down, move the hard drives to the spare, and I'll have the mail server back up within 5 minutes. Not bad for a cheap little box.
lf(1): it's like ls(1) but sorts filenames by extension, tersely
Virtualized NTP is about the dumbest thing I've read on /.
Yes, worse than various conspiracy theories and fanboi wars.
Last generation's compute nodes. We keep some around for utility functions after decommissioning a large cluster.
Go get a GPS satellite receiver/time server. Actually, get two. Don't screw with time.
THEN, virtualize the rest of the stuff. Monitoring, syslogging, management, patchers, etc.
We've virtualized everything except for
- a Windows DC so that it stays up if the vmware datastores or SAN eats itself in a horrible way.
- The NIS server we have to use on our UX environment due to an ancient regulation. I'm not willing to put up HP-UX VMs for this right now, otherwise it'd be safe in a VM as well.
- Anything we can't virtualize due to licensing/contract/support issues. So our VOIP environments, phone call recording, access control systems for the doors,
My datacenter is getting a lot nicer to look at, and a lot easier to upgrade. I can shift servers or volumes all over the room so I can do live maintenance during the day.
My mom says I'm cool.
Those support tasks don't exactly push hardware to its limit, and most of those tasks are the kind of thing that demands a bunch of redundant servers anyway.
Throw a bunch of "last generation" hardware at the task -- stuff from the "asset reclamation" pile. Leave a few more around as spares. Less disposal paperwork. Works just fine. By the time your last spare fails, you'll have a new generation of obsolete hardware.
--
To be fair, if someone cares enough about time accuracy to understand why that's a dumb idea, they should probably be using a GPS receiver instead of a PC.
NTP server is all about consistency. If it's running in a VM and can be delayed at the whim of the host, do you think it's going to be a very good source of time?
If you can't run it on your iPad, it's probably not worth running.
--Management.
rewriting history since 2109
There are good reasons to separate functions. Mainly security. That way, if someone hacks the NTP server, they don't get control of DNS, nor do they get control of the corporate NNTP server, or other functions.
The ideal would be to run those functions as VMs on a host filesystem that uses deduplication. That way, the overhead of multiple operating systems is minimized.
What would be nice would be an ARM server platform, combined with ZFS for storing the VM disk images, and a well thought out (and hardened) hypervisor. The result would be a server that can take one rack unit, but can handle all the small stuff (DNS caching, NTP, etc.)
Uhhh. because the "little boxes" and individual servers run on unicorn farts and angel tears?
NTP servers are NOT about consistency, they are about making badly designed protocols, such as NFS, capable of limping, instead of just falling on their face.
If the requests on these protocols used a client timestamp for the client's idea of the current time, then the server on receiving the request could look at its idea of the current time, and arrive at a delta before it actually did anything other than enqueue the request locally.
Then when the server responded with a non-"now" timestamp in any client response, it could apply this delta to the response value, and as far as the client was concerned, it and the server would have synchronized ideas of "now", without resorting to all of this NTP BS or worrying about clock drift, or anything.
I lobbied very strongly to try to get this fixed in NFSv4; maybe we will get our collective heads out of our butts by NFSv5.
...I don't want it in my datacenter. If you have no budget for non-revenue-generating boxes for services like DNS, NTP, etc. then upgrade the server hardware you tore out of production after the last upgrade cycle with SSDs and low-wattage processors & put it back into service for your internal needs.
Otherwise get a few Dell R210s or some other small cheap rack server with an IPMI 2.0 BMC and get on with your business. Any money saved by buying "mini-PCs" (or whatever you want to call them) for any datacenter computing hardware you plan to rely upon at all will be burned the first time you have to drive to the datacenter and physically babysit some cheap machine because it didn't have IPMI.
Answer: VMware VMs.
"Flyin' in just a sweet place,
Never been known to fail..."
Well, one of the reasos is that some services get hold of port 80 (or, a few times other ports), and don't want to share it. With virtualization you can share resources with those too... But yes, those services are a minority, and probably won't need a lot of resources...
Another reason is that you may want to give different people permission to administrate different machines... But again, except for companies that sell hosting, that's an exception.
A third reason is that you may want to replicate your environment for backups and testing... Except that you don't need a VM to do that on Linux. You just copy the files, add two devices to /dev and run the bootloader again. It's easier than backing-up a VM in Windows.
And I've never heard about any other reason for virtualization. I can't also think about any other. I'm lost about why sudenly so much people wants it so badly... Ok, all datacenters added specialized machines for decades because of those first two reasons I gave you above, and get some benefit virtualizing them... But the core of a datacenter (the main databases, web servers - the machies that actualy spend the day working) should run on the metal, and altought I've met several people that arguee otherwise, I've never heard any argument for virtualizing them that holds any water.
But now, I think, maybe the HA people should try to virtualize their clusters. They have a huge amount of redundancy, and consolidating several virtual machines in a single real one can help them reduce their costs. (Ok, if you are in doubt, no, I'm not THAT stupid, it's a joke.)
Rethinking email
I don't operate a datacenter, but for virtualized servers in an office, I always enable the NTP server functionality in the hypervisor, have it sync to a stratum-1 time source, then advertise that address via DHCP and DHCPv6 for my guests and workstations (and visiting cell phones) to use. Being the definitive time source, I also tell the hypervisor to automatically set the clock on the guests, then give a virtualized AD domain controller (if any) the PDC FSMO role to set the Windows domain time. I have sites with two or three hypervisors running NTP, and it seems to work well. Not sure if it will scale to your environment, OP, but it may be worth mulling over.