31
votes
Disable hyperthreading from within Linux (no access to BIOS)
Newer Kernels provide a Simultaneous Multithreading (SMT) control.
You can check the state of SMT with;
cat /sys/devices/system/cpu/smt/active
Change the state with
echo off | sudo tee /sys/devices/...
17
votes
How do I stop Dell R730xd fans from going full speed when Broadcom/QLogic NetXtreme 57711 PCI card added?
After tearing my hair out on newly arrived lovely R730xd with 16 3.5" disk slots spinning fans at 15k RPM when Intel X520-DA2 10G card is in any PCI slot, I've found following solution for CentOS ...
- 473
14
votes
Disable hyperthreading from within Linux (no access to BIOS)
A script to disable hyperthreading in the machine startup...
To disable hyperthreading I include a script on machine /etc/rc.local. It is not exaclty clean, but is easy to install, independent of cpu ...
- 523
13
votes
Purpose of vent holes on the top of rackmount servers?
(Some people are hard to please...)
These are likely system exhaust vents and fit into the total design of the product. Please understand that the system is designed and optimized for rack mounting ...
- 197k
13
votes
Accepted
How to directly add an SSD to a PowerEdge server without entering BIOS or creating a Virtual Disk?
Required Note: I work for Dell
In order to get the system to "see" this first SSD, I first had to use the BIOS to create a Virtual Disk representing that Physical Disk. This was frustrating ...
- 1,068
11
votes
How to install ZFS on Dell Poweredge server and Dell disk array without using the RAID controller
It depends:
H200/300 and PERC9 (ie: 330, 730, 830) cards have the capability to work in pass-through mode, meaning that the disks can be directly presented to the operating system. To do that, you ...
- 48k
11
votes
Accepted
Can we upgrade Dell's basic Server R240 (which still uses HDD 7200RPM) to an SSD?
On Dell's R210, R220 and T130 I've successfully used Sandisk's consumer grade SSDs for years. I've done this with PERC's H410 and H710 controllers.
It will be a matter of controller and controller's ...
- 1,709
10
votes
Disable hyperthreading from within Linux (no access to BIOS)
You can use the "thread_siblings_list" for each core to turn off the second core in the HT pair.
The following command pipeline is hacky, not optimised, and done this way hopefully to make it easier ...
- 583
9
votes
Accepted
Dell PowerEdge T310 won't POST after memory upgrade
Take a look at the technical data sheet for your memory.
Specifically, the HMT31GR7BFR4A you have is dual-rank, not quad-rank.
Your system probably does not support dual-ranked 8 GB for 32 GB total (...
- 1,556
9
votes
Can we upgrade Dell's basic Server R240 (which still uses HDD 7200RPM) to an SSD?
Yes, you can swap HDDs <-> SSDs the way you want. Moreover, it's OK to use non-Dell branded SSDs inside Dell servers, you won't receive support (of course!) and some functions won't work like LEDs, ...
- 13.7k
9
votes
Differences between HW RAID and ZFS
Hardware RAID vs ZFS doesn't make a lot of difference from a raw throughput perspective -- either system needs to distribute data across multiple disks, and that requires running a few bit shifting ...
- 3,327
8
votes
Accepted
Max drive size for PERC H700 in Dell r610
Just to share my config, i got a PERC H700 (inside a R410 server) with the firmware version 12.3.0-0032 and my 4 new hard drives IronWolf 10 TB are seen as 2 TB drives. After upgrading the firmware to ...
- 1,709
7
votes
Dell PowerEdge R200 won't boot, has flashing green and blue lights
Well, right up front, let me tell that the outlook is not good. 10:1 (at least) that your motherboard is bad and needs to be replaced.
The standard troubleshooting approach to this problem is to ...
- 53.8k
7
votes
Accepted
control a server before the OS loads
Your server should have DRAC available and there are most likely upgrade licenses available to allow full remote management capabilities (including remote video that works completely without OS). DRAC ...
- 98.8k
7
votes
Accepted
E3-1240 v5 cpufreq-info says: "no or unknown cpufreq driver is active on this CPU"
Modern Intel processors use P-states for CPU frequency control. When Linux is using this driver, it will be visible thus:
# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver
intel_pstate
The ...
- 244k
7
votes
Accepted
Can I configure AC Power Restored option via iDRAC on a Dell PowerEdge server?
Although Twisty's solution is probably the easiest, it requires OMSA to be installed.
You actually can change this setting using the iDrac8, but from command line only.
To do so, SSH into the idrac (...
- 644
7
votes
Accepted
Upgrading existing environment to vSphere 6.5
1) Backup everything with Veeam
2) Decomission one host from your ESXi 5.0 cluster
3) Create one-node ESXi 6.5 cluster from decommissioned in (2) host
4) Restore VMs from your backup to your new ...
- 13.7k
7
votes
Accepted
How to upgrade iDRAC firmware and BIOS of Dell PowerEdge R510?
As shown in the training video in section 4 of the support article Dell PowerEdge: How to a Remote Firmware Update with the iDRAC?, you must manually unzip iDRAC6_1.85_A00_FW_IMG.exe and upload the ...
- 6,005
7
votes
Dell PowerEdge T310 won't POST after memory upgrade
Diagnostic lights 1 and 4 means system board failure. Either you have the incorrect RAM, A bad ram stick or a bad system board. I looked at the firmware updates and none address an issue with ram.
- 1,170
7
votes
Dell R730xd - Best way to configure storage for simultaneous use with ZFS & Hardware RAID
Regarding your question about splitting the backplane across controllers, yes, it's possible. I've done this with 8-bay enclosures where two 4-lane SAS SFF-8087 connectors were present. 4 disks to one ...
- 197k
6
votes
Disable hyperthreading from within Linux (no access to BIOS)
Disable SMT / HT at boot time using the kernel command line parameter nosmt:
nosmt [KNL,S390] Disable symmetric multithreading (SMT).
Equivalent to smt=1.
...
- 161
6
votes
Accepted
Quieting down a Dell PowerEdge r710
This is an enterprise-class server. It's doing what it was designed to do... You're using it in a manner in which it was not intended... I wouldn't recommend altering the hot-swap fans or power supply ...
- 197k
6
votes
Accepted
ZFS on enterprise RAID pass-through, and ZFS on FreeBSD root
You can control the PERC H730 and H330 using the LSI MegaCLI utility as both of these cards are Dell PERC badged LSI cards.
There is an excellent article and tutorial on how to do this at https://...
- 6,783
6
votes
Accepted
How to connect two Dell storage arrays to a to a Dell Poweredge server (daisy chain vs direct)?
You can stack the MD unit that way; (In the image its 3 MD, but you can see how)
For your openmanage question, yes, it can be used remotly, but be sure to set the routing correctly in the management ...
- 16.8k
6
votes
How safe is Raid 0 with Perc710P hardware raid controller?
Regardless of how RAID 0 is implemented it works the same way, it does not include fault tolerance. If a disk fails you will loose access to the RAID 0 volume. If you want fault tolerance for your ...
- 3,254
6
votes
High pitched noise on PowerEdge 1950
It's probably screaming to be put out of its misery. Seriously, thats a 12+ year old server you got there. They are easy to take apart and investigate. I'd get out a thing of canned air, take out the ...
- 25.6k
6
votes
Recover data from failed RAID 5 Dell Poweredge T710 Server
Wow. This question. Another example of what not to do. You don't have appropriate backup methods in place. You don't know if your backups are any good and have no good way to test them. You have data ...
- 110k
6
votes
Dell PowerEdge R7525 + Nvidia A16
(I work for Dell) - specifically, I do a lot of optimization.
I think you're tracking a bit off course; "Above 4G decoding" is a feature left over from when BIOS PCIe memory enumeration was ...
- 1,068
5
votes
Accepted
Windows Server Backup Fails: There is not enough disk space to create the volume shadow copy...
Change your VSS for the system partition to use the C:\ at present it doesn't have enough space to create VSS for itself so fails the backup.
- 66
5
votes
Any trick to connect to the DRAC console from a mac?
For DRAC5 you don't need to use any virtual machine with Windows or Linux. Just do some simple java configuration (for Java8u31 and later).
If you have not already installed Java install it link or ...
- 231
Only top scored, non community-wiki answers of a minimum length are eligible