Linux
How To Determine Which Network Interface Belongs To Which PCIe Device
If you have physical access to the system, you can identify with 'ethtool -i' which will blink the NIC. How the NIC blinks depends on the model. The Mellanox cards have an orange light on the PCB that will blink. ~$ ethtool -p enp33s0 If you are ...
How to generate a Mellanox log bundle
Mellanox uses their tool 'sysinfo-snapshot' to collect information from the system and their components. The tool is attached to this article. After downloading, extract it and run with the suggested flags tar -xvf sysinfo-snapshot-3.2.3.tar cd ...
How to Install and Use SM-Lumberjack on Linux
Description: Lumberjack is a non-invasive, diagnostic shell script which collates command outputs along with important system files and logs, creating a single compressed tar archive as output. The following operating systems are supported: RHEL 6/7 ...
How To Diagnose Memory Errors on AMD x64 using EDAC
Find the first DIMM slot using dmidecode output ******************************************************************************* 1. Which EDAC modules are in use? This HowTo is for the amd64_edac module. # lsmod | grep -i amd amd64_edac_mod ...
Over-provisioning SSDs
Over-provisioning sets a percentage of the usable space on a hard drive to be locked away in the Host Protected Area (HPA) of the drive's firmware, ensuring that the disk never hits 100% capacity utilization, for performance and endurance ...
Default credentials (Linux)
Q: I just received a system with a pre-installed Linux operating system. What is the password for logging into the system? A: This will depend on the distribution we installed, as various distributions can carry different default access policies. The ...
Install a GUI to Redhat Enterprise Linux 7.1
If you have performend a RHEL 7 Linux Server installation and did not include a Graphical User Interface (GUI) you can do it later directly from command line using the yum command and selecting an appropriate installation group. To list all available ...
Updating MAC Addresses (CentOS/RHEL)
If your system's motherboard has recently been replaced, you may encounter network failures due to the new motherboard using different MAC addresses. Modern Linux distributions such as CentOS and Red Hat will typically auto-populate udev rules and ...
Installing a GUI on Ubuntu Server 15.04
You have just received your new server running Ubuntu 15.04 and realize that you would now like to have a GUI installed instead of using it through the command line all the time. Here is what you do. 1. Update the server and enter password 2. ...
Routing Multiple Nic's within the same subnet
You may find that when working with multiple Ethernet cards within the same subnet that outgoing traffic may default to only one Nic. This is due to the routing table that Linux uses by default and while this works in most cases, you may want to ...
Identify Bad DIMM from EDAC
Here is an example to show you how to identify defective DIMM on an AMD_x64 archtecture machine, syslog reported kernel error from EDAC (Error Detection and Correction kernel module). Here is a piece of typical error message from EDAC kernel: ...
MDADM - Monitor Mode with Email
You can run mdadm as a daemon by using the follow-monitor mode. If needed, that will make mdadm send email alerts to the system administrator when arrays encounter errors or fail. Also, follow mode can be used to trigger contingency commands if a ...
MDADM - Common Commands
1. Create a new RAID array Create (mdadm —create) is used to create a new array: 1 mdadm --create --verbose /dev/md0 --level=1 /dev/sda1 /dev/sdb2 or using the compact notation: 1 mdadm -Cv /dev/md0 -l1 -n2 /dev/sd[ab]1 2. /etc/mdadm.conf ...
Create a Bootable Linux USB Flash Drive Using dd
Insert your USB drive into your computer and use ‘df’ or ‘lsblk’ from the command line to determine the device name your flash drive has been assigned, e.g. /dev/sdb, sdc, etc. Make sure the drive is not mounted. If necessary, unmount it with: sudo ...
Installing NVIDIA drivers for Ubuntu 14.04/16.04 with multiple graphics adapters.
Generally the NVIDIA Linux drivers work with most of their cards. Some cases with Tesla's and higher end cards may have slight differences. The cards I'm working with today are the Quadro and Geforce series. FIRST Make sure your primary card is in ...
How to Create and Boot from a LiveCD/USB Drive
STAGE 1: Download .ISO image, prepare USB flash drive First, you will need an .ISO image of a Linux OS that you will put onto a USB drive (4GB+ recommended). As far as .ISO images go, you can use one from any OS that you wish. We strongly suggest ...
Installing Ubuntu Server with the OS on Software Raid 1 and Software Raid 0
Setup Ubuntu 14.04.5 LTS Server with Software Raid1 for OS. (Video)
The attached video will demonstrate a complete Ubuntu 14.04.5 LTS Server setup with the following. Legacy Bios Mode. 240 GB Raid 1 - 2 X 240 GB SSD - OS drive 800 GB Raid 0 - 2 X 400 GB SSD - SCRATCH The video is approximately 6 Minutes and ...