Category Archives: Linux

FreeBSD commands

The purpose of this post is to provide useful command needed while working on freebsd: How to check ipv4 routing table: netstat -rn -4 How to install a package: pkg install apache24 How to get list of software installed in … Continue reading

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Understanding ls command output

ls command provides information about a file.  In Linux everything is represented as a file. A sample output of ls -lh is give below. Total: show total size of the folder. File type: First field in the output is file … Continue reading

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iptables in ubuntu

iptables can be used to inspect, modify, forward, redirect, and/or drop IPv4 packets. There are five table in iptables: 1> Raw 2> Filter 3> Nat 4>Mangle 5> Security To view these table we can use following command: iptables -t raw … Continue reading

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Understanding ntpq output

In Ubuntu NTP configuration is kept under file /etc/ntp.conf ntpq> peer remote refid st t when poll reach delay offset jitter ============================================================================== ntp.ubuntu.com .POOL. 16 p – 64 0 0.000 0.000 0.000 *123.108.200.124 210.23.25.77 2 u 83 128 375 241.212 … Continue reading

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Routing and NAT in Ubuntu with the help of iptables

This post can be used in case when we have a Device having Ubuntu OS and with two or more NIC. One NIC is having internet connection and on another NIC some host/devices are connected. Goal of this post is … Continue reading

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Tiny Core Linux

How to get into root: sudo su Default user is tc and password is not set for the user to set the password for tc user use following command: passwd Change ip address of interface in tiny core: ifconfig eth0 … Continue reading

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Untar files in linux

To extract the tar file use following command: tar -xf <name of the file> To extract file to a new directory use following command: mkdir techsupport && tar -xf techsupport.tgz -C techsupport

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