How do I bind NIC interrupts to selected CPU?

I read this interesting mailing thread few weeks back. I won’t be late to share this with open source enthusiast like you. Here goes the story: I have a 4 Quad server, am trying to bind NIC eth0 interrupt(s) to CPU4 and CPU5. As of now, my eth0 is found bind to all the 8’s. #grep eth0 /proc/interrupts | awk ‘{print $NF}’ | sort eth0-0 eth0-1 eth0-2 eth0-3 eth0-4 eth0-5 eth0-6 eth0-7 How to move ahead? Solution: Follow these steps to get it done. As I am using Broadcom card(bnx2), I am going to run this command and reboot my machine. Open...

Puppet Module for JBOSS

Recently one of my colleague called me up with a problem statement where he was finding difficulty configuring JBOSS through puppet. I tried to help him through one of VMware Workstation box on my Dell Inspiron. I tried to google but couldn’t find the working example. I tried my hands of my own and YES…I did it finally. I am sharing the overall idea how to deploy and configure JBOSS through Puppet. Let’s say you have the following steps which you manually perform for installing JBOSS on your Linux machine: 1.$ su -c “yum install java-1.6.0-openjdk-devel” 2.$ java –version 3.wget...

Automated shutdown of ESXi and VMs through Powershell

My friend was running a cybercafe center. He has dozens of ESXi running 100 of VMs. He was using Dell Multi-UPS Management console to handle his small computer center. The very often power cut was ruining his business. He called up me to see there is a possible solution to handle graceful shutdown of VMs and then ESXi through the available tools and technique. This solution really helped us to handle the situation gracefully. I just noted down the steps roughly and will not be late to share it with you: 1. Download the Dell Multi-UPS Management Console from http://www.dell.com/support/home/us/en/19/Drivers/DriversDetails?driverId=R318771 2....

Installing Java Development Toolkit (JDK) on Linux

Installing Java Development toolkit on Linux is always matter of difficulty since Oracle provides both RPM and tarballs in their official website. Installing RPM is pretty simple but installing through tarballs need sufficient environmental variable declaration which is little different from Windows Operating System. Follow the steps mentioned below to install java-1.6. 1.Download jdk-6u16-linux-x64.bin (From the URL mentioned in the prerequisites section) to /opt directory. 2.Change the permission of jdk-6u16-linux-x64.bin file to 755. [root@bang opt]# chmod 755 jdk-6u16-linux-x64.bin 3.Execute the jdk-6u16-linux-x64.bin file to start installation. [root@bang opt]# ./jdk-6u16-linux-x64.bin Sun Microsystems, Inc. Binary Code License Agreement for the JAVA 2 PLATFORM...

How to setup Domain Name Server (DNS) on Linux?

It has been long I was thinking of writing something about DNS(Domain Name Server). DNS is a database of the IP to Name and Name to IP conversion.I went through lots of tutorials related to DNS but couldnt satisfy myself unless and until I started writing commands and configuring files for the initial setup.After lot of tweaking and command line I was able to setup a simple DNS server. Lets travel into the world of DNS. I have a RHEL 4 Machine ready with bind packages installed.The Minimal requirement are: [root@localhost ~]# rpm -qa bind* bind-libs-9.2.4-24.EL4 bind-utils-9.2.4-24.EL4 bind-9.2.4-24.EL4 bind-chroot-9.2.4-24.EL4 bind-devel-9.2.4-24.EL4...

How to test Multicast Packet Filtering?

Today morning I started my day testing with Multicast Packet Filtering. I had buntu 12.04.1 and CentOS 6.5 in my VM running over ESX 5.5.I decided to make CentOS as Client and Ubuntu as server for the setup. First of all, I downloaded iperf as I had no YUM working at my internal lab. Its simple to install,download the package and install. Luckily, I dint get any dependency hell. On Ubuntu Box: SERVER MACHINE ===================================== sudo iperf -s -u -B 224.0.65.68 -i 1 ————————————– server listening on UDP port 5001 Binding to local address 224.0.65.68 Joining multicast group 224.0.65.68 UDP...

Understanding /proc/cpuinfo

A hyperthreaded processor has the same number of function units as an older, non-hyperthreaded processor. It just has two execution contexts, so it can maybe achieve better function unit utilization by letting more than one program execute concurrently. On the other hand, if you’re running two programs which compete for the same function units, there is no advantage at all to having both running “concurrently.” When one is running, the other is necessarily waiting on the same function units. A dual core processor literally has two times as many function units as a single-core processor, and can really run two...

How to setup vsFTP server on Linux?

FTP refers to File Transfer Protocol. By default, Red Hat supports vsftp. If you do minimal RHEL installation, you mightn’t have vsftp related RPM packages installed. To setup an anonymous ftp server on Red Hat Enterprise Linux, follow these steps: 1. Verify that the vsftpd package is installed. #rpm -qa |grep vsftpd If it is not installed, the install it as follows: RHEL 3 and 4 # up2date -i vsftpd RHEL 5 # yum install vsftpd 2. Verify the localhost line in /etc/hosts looks like the following: 127.0.0.1 localhost.localdomain localhost 3. Next configure the vsftpd.conf file. NOTE: Back up the...

How to increae Swap space under Linux

“Can Linux be installed without swap space?”. This question was asked to me on one of Linux System admin interview. It might confuse anyone who is still fresher and have no hands-on experience with swap terminology.But the reality is “Yes”. But if you did this, you should be ready to cope up with your Linux box next time you put extra load on your box.It will crash someday.Its always recommended to provide extra space for swap partition.Swap is only used when you have maximum load. This article discuss how to increase the swap space through adding swap file on Linux...

How to setup Centralized Logging System on Linux?

I was just hanging around blogs until I cam across one nice piece of setting up centralized Logging setup.I thought to try it out of mine and here is the output:Syslog is a fantastic facility for logging on Linux machines. Lets say you have a small number of servers, and want to log them all to one central syslog server. Here we’ll describe a simple configuration. 1) Setup the syslog serverOn the system you want to use as the syslog server, edit the file /etc/sysconf/syslog, and add ‘-r’ as follows: Options to syslogd -m 0 disables ‘MARK’ messages. -r enables...