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45
votes
3answers
2k views

Assessing equipment damage following a lightning strike - Should I have planned more?

One of my client's sites received a direct lightning hit last week (coincidentally on Friday the 13th!). I was remote to the site, but working with someone onsite, I discovered a strange pattern of ...
33
votes
6answers
23k views

How do I permanently disable Linux's console screen saver, system-wide?

I've got an Ubuntu server that boots up in text mode. It rarely has a screen or keyboard attached to it, but when I do attach a screen, I usually have to attach a keyboard too, because the darn ...
30
votes
9answers
17k views

Does CPU power management affect server performance?

I was doing some simple hand benchmarking on our (live) database server during non-peak hours, and I noticed that queries returned somewhat erratic benchmark results. I had enabled the "Balanced" ...
25
votes
2answers
7k views

Disable CPU Scaling in Windows Server 2008 R2

How do you disable CPU power management scaling in Windows Server 2008 R2? After setting the Control Panel, Power Management plan to performance and then rebooting -- CPUID's Cpu-Z still shows the ...
23
votes
6answers
5k views

Best practices for power cabling racks in DC

With network cables it is easy. I use velcro-ties, coloured cables, 0U vertical cable organizers from APC on side of the rack -- easy and neat. However with power cables it was always giving me ...
21
votes
16answers
1k views

How have you saved green by going green?

For the purpose of this question, I am interested in server/datacenter related hardware. Have you had any measureable amount of ROI by swapping existing hardware to more "green" or energy efficient ...
18
votes
7answers
664 views

Power loss at company

Property management at my organization has informed me that our building will be losing power for 4 hours tomorrow. I need to be prepared for this event (we're a small organization, i'm young, ...
12
votes
12answers
25k views

What is the lifespan of an typical UPS battery?

When using a uninterruptible power supply how long does it preserve the original capacity? Say I buy a UPS that holds the necessary load for 10 minutes - I don't want it to unexpectedly come into ...
10
votes
6answers
6k views

Automatic shutdown when idle?

We have about 600 Windows XP PCs in a school of about 2000 students, the majority of the PCs are in ICT suites and class rooms. It is a regular occurance that half of the computers are left on ...
9
votes
4answers
439 views

Maxing out both PDUs in a rack with redundant power

If I have a rack full of servers using redundant power supplies, and I'm keeping the amps at 80% (16A of 20A), isn't this still asking for trouble in the event of a power loss on one of the circuits? ...
9
votes
1answer
304 views

Sysadmin in the Developing World: What are the differences between various kinds of power protection?

Hello I'm an ICT (InfoComTech) US Peace Corps volunteer deep in Tanzania who has the task of managing and advising concerning our college's two SunFire Sun Ray Servers and Dell Proxy server (on 2 ...
8
votes
3answers
530 views

Power Cables Required to Switch from 120v to 240v for Dell Poweredge Servers

We have a cabinet of servers and other hardware (switches, firewalls, etc) that all are currently running on 120v. I've confirmed that the power supply for all of our devices support both 120v and ...
7
votes
4answers
13k views

Why do I need a raid battery pack?

I'm trying to understand why one would add a batterypack to a raid card. It seems to me like if power goes down, running just the raid card is going to do little good: without power for HDs and ...
7
votes
3answers
7k views

How do I configure Ubuntu Server to power down drives when not used?

I just got home file server, and it contains 7 hard drives. I installed on it Ubuntu Server (Jaunty). What should I do to make it power down drives when they are not in use (most of the time they will ...
7
votes
7answers
400 views

What less obvious ways are there to misuse and damage a UPS?

I've never had an uninterruptible power supply and think of buying one. What not-so-obvious things should I not do to the UPS so that it lives longer? I don't mean some obvious abuse like ...
7
votes
2answers
388 views

Green-IT: How do you deal with poweroff systems in your system monitoring?

Many of you probably have completed or are contemplating Green-IT projects with the goal to power off idle or unneeded systems when demand for computer resources is low: How you did handle this ...
7
votes
2answers
538 views

Vista Power Management GPO

I've created a loopback GPO that has several settings (both computer and user) including a Custom User Interface (Access 2007 Application) and Power Management (has the computer sleep after being idle ...
6
votes
7answers
1k views

Is there a solution against short power outages except UPS?

I encounter very short power outages quite often. Typically they last for just couple of seconds - perhaps the power grid maintenance staff just flips the switch to "Off" and then immediately to "On". ...
6
votes
6answers
485 views

Will wear induced by turning computers off in the evening be offset by energy savings?

I'm asking this here because this is primarily a huge office scenario and administrators will more likely have the answer I'm looking for. Employees' desktop computers can be either left turned on ...
6
votes
5answers
9k views

automatically shutting down an ESXi host nightly

We just picked up a new development server that I've loaded ESXi on. The room it's in is well ventilated during the day but at night the door is closed and it gets quite toasty in there. I've been ...
6
votes
6answers
1k views

Server power supply failures?

I have 6 servers both with 2 power supplies attached to an UPS. I want to add 4 more servers but the UPS is full and due to budget restriction I couldn't buy a new one for months. The 6 + 4 new ...
6
votes
3answers
19k views

How to disable all power management in Ubuntu (for a server netbook)?

I need to disable everything related to having the netbook-server go into sleep/hibernate/shutdown. Spinning down the disks during inactivity is fine, but it is crucial that the machine remain in a ...
6
votes
3answers
1k views

Open source DCIM stack?

Our 500-server data center is growing quickly and my manager has started investigating using a specialized Data Center Infrastructure Management (DCIM) package to help manage constraints. DCIM ...
5
votes
1answer
79 views

Power Control Compartment?

I recently purchased an IBM enclosed, rolling rack that had a 6 drive server, huge battery backup, and this strange item called a "Power Control Compartment" I cannot find any good documentation ...
5
votes
1answer
104 views

Using more than 80% power on a circuit in a disaster scenario

We currently have two cabinets of equipment at our datacenter, and each cabinet is served by two 30A circuits. The facility is relatively new, and each circuit is (supposedly) redundant at the source. ...
4
votes
3answers
364 views

Proof that hibernating the server over the weekend is not a good practice

Is it true that the life of the modern server machines is longer if you never turn them off instead of turning them off when not needed? I am talking about database server machines that are not used ...
4
votes
5answers
2k views

Will 208v Hurt My Servers?

I've decided to move most of my servers out of our closet at work and into a datacenter. All of our servers are 110v, however we're starting to purchase some new ones, and the datacenter tech ...
4
votes
1answer
633 views

How does a CPU ever go Idle enough to enter deeper C states?

Even if no user process is running, don't the kernel processes keep the CPU active enough so as to prevent it from entering a deeper C state like C1 or C2 ?
4
votes
1answer
637 views

How to DISable display sleep on Dell PowerEdge R310

The display on these PowerEdge systems goes to sleep after some period of time. Normally, when you plug in a KVM, you have to press a key to "wake up" the display. I'm connecting these servers to a ...
4
votes
2answers
2k views

Get drive power state without waking it up

Is there any way how to determine whether some drive is sleeping without occasionally waking it up? I have tried hdparm -C and smartctl -i but both of them actually wake it up when its already ...
4
votes
1answer
5k views

How to enable hibernation on Windows Server 2012 with Hyper-V role? [duplicate]

I have Windows Server 2012 installed on a laptop. I need a server because I develop software that I need to test specifically on a server edition. Documentation for Windows Server 2012 says Sleep ...
4
votes
1answer
1k views

How do I inform my ESXi 5 host(s) of a power outage?

My APC UPSs all have the APC SNMP card so they are able to communicate over the network. From what I've been able to find the PowerChute program alerts the guest OS that a power outage has occurred ...
4
votes
2answers
1k views

How can I get FreeNAS to respond to libvirt shutdown requests

I have a KVM VM of FreeNAS 0.7.1 Shere (revision 5127) running on Ubuntu Server 10.04 and I'm unable to convince the VM to shutdown from the host virsh shutdown freenas I would expect this to send ...
4
votes
2answers
537 views

How can I monitor whether my HDDs are in standby?

How can I monitor if/when and for how long my hard drives go into standby? I've a Windows Server with a RAID5 (software) for data and another regular disk on which the OS is installed. I want to make ...
3
votes
6answers
5k views

Redundant Power Supplies and UPS (Dell Servers)

I have a number of Dell 2950 servers with two power supplies. In normal usage how are the PSU's utilised? Do they both draw '50%', only switching to 100% if one of them dies? Does one supply provide ...
3
votes
4answers
588 views

Best way to execute a command after Linux system halt

Problem: The SSDs in our servers require a power cycle (i.e. off/on, not reset/warm reboot) after a firmware update. Thoughts: Using 'ipmitool chassis power cycle' I can cycle the server's power. ...
3
votes
3answers
334 views

Testing UPS output for 'clean' power

Is there any way to test the 'cleanliness' of the power your are getting at your PC from the UPS and also from the wall? I have a powerful workstation (Dell T7400) that is now on its 3rd PSU in 30 ...
3
votes
3answers
2k views

How to measure server power consumption?

We have data center running more than 2000 servers. We are planning to shutdown the servers on a weekend for cost cutting purpose. How can we calculate which servers are consuming more power in the ...
3
votes
2answers
303 views

Power reading 2 amps with 13 servers?

We have a rack in a data center and we became suspicious of running out of power. But our power bar says 2 amps! It has a live indicator, so it's not just one reading. Do you think there's something ...
3
votes
1answer
202 views

Turn server back on after power loss with FreeBSD

I have a VIA M'SERV S2100 with FreeNAS 8. Since I upgraded from FreeNAS 7, the M'SERV no longer turns back on after suffering a power failure. As I remember it, there was a setting for it in the old ...
3
votes
2answers
3k views

OpenWRT USB attached disk spin-down

I use a couple of ASUS WL-500GP running OpenWrt Kamikaze 8.09.1 (2.4 kernel) as small office gateways and firewall. Now I would like to attach USB disks to cache local backup-data during office-hours ...
2
votes
2answers
10k views

How to enable sleep/standby on Windows Server 2012 Hyper V

I know it's possible because sleep works in HyperV under Windows 8. edit: I know this is probably not "supported".
2
votes
3answers
626 views

How to set finer-grain HDD Sleep settings in Mac OS 10.5?

Is it possible to specify how many minutes of inactivity Mac OS should wait before it sleeps hard disks? Is there a plist I can manually specify "60 minutes" or something? The GUI gives you the ...
2
votes
5answers
223 views

VOIP Power outage strategy

In the past 2 years, we have had 4 instances where we have been without power for a period of 4-6 hours - due to construction crews cutting power lines, car accidents involving downed power lines, ...
2
votes
5answers
694 views

Need hardware to remotely reset hosted computers

We host computers and servers for clients. When their machines crash we need to reboot these machines. However this is not possible when we are out of the office. I know on servers such as HP you ...
2
votes
4answers
3k views

HP ProLiant ML110 G7 Questions

Have an HP ProLiant ML110 G7 running Server 2008 R2. Question #1: This server takes FOREVER to boot. I think it's because of "HP Power and Thermal Calibration" it does at the beginning of every ...
2
votes
5answers
9k views

How to find out if my Dell R210 server has iDRAC with shared network connection or dedicated?

My server is Dell R210 and it is colocated. I need to find out whether the iDRAC BMC on this particular box has dedicated ethernet connector or is it shared. Also - do I always need separate IP ...
2
votes
2answers
1k views

Is there a dynamic power consumption equation for RAM?

How is the dynamic power consumption of memory determined . Can anybody give a canonical equation for power consumption of the RAM. What are the parameters involved in determing the dynamic power ...
2
votes
2answers
509 views

A/B Power Configuration for Server Cabinet

I'm upgrading our cabinet at our colocation for A/B power and wanted input on which of our options are good or bad. First, a bit of an overview of our setup: We currently have a single circuit feed ...
2
votes
1answer
695 views

Will a 20 Amp Circuit Work for 2 servers with 2 PSU ea. needing 9.2 Amp Input Requirement per PSU?

I'm a bit new to the power calculations for electricity at a colocation facility. I have 2 HP DL580s that are pretty maxed out and this is what the HP power calculators gave me for each server. Total ...