Author Archives: simonljb123

How to use ssh/scp without password on CentOS 6.4

On server (192.168.0.2): Generate keys: # ssh-keygen -t rsa press enter for all Copy the public key onto the other server (192.168.0.3) # ssh-copy-id -i /root/.ssh/id_rsa 192.168.0.3 Now you should be able to ssh/scp to 192.168.0.3 on 192.168.0.2 without password. Advertisements

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How to change the numeric order of Network Interface on CentOS 6.4

Edit /etc/udev/rules.d/70-persistent-net.rules: You can change the NAME into eth0, eth1, eth2, eth3, etc to change the order. # PCI device 0x10ec:0x8168 (r8169) SUBSYSTEM==”net”, ACTION==”add”, DRIVERS==”?*”, ATTR{address}==”xx:xx:xx:xx:xx:xx”, ATTR{type}==”1″, KERNEL==”eth*”, NAME=”eth0″ # PCI device 0x10ec:0x8168 (r8169) SUBSYSTEM==”net”, ACTION==”add”, DRIVERS==”?*”, ATTR{address}==”xx:xx:xx:xx:xx:xx”, ATTR{type}==”1″, KERNEL==”eth*”, … Continue reading

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Basic Understanding of PATH in Linux

According to LINFO, PATH is an environmental variable in Linux and other Unix-like operating systems that tells the shell which directories to search for executable files in response to commands issued by a user. For example, when you want to … Continue reading

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Install and Configure Master and Slave DNS Servers on CentOS 6.4

Assume the master server’s IP is 192.168.1.2, and the slave server’s IP is 192.168.1.3. Before you start, make sure you have installed caching only DNS server on both the master and slave servers.  Refer to this post for caching only server … Continue reading

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Install and Configure Authoritative DNS server on CentOS 6.4

Assume the IP of the authoritative DNS server is 192.168.1.2, and the server IPs used in the data files are 192.168.1.3 and 192.168.1.4. Before reading the rest of this post, make sure you have installed caching only name server as … Continue reading

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How to disable remote root login in Linux

For security purposes, you’ll want to disable remote root login for your server to prevent hacking. # vi /etc/ssh/sshd_config find the line: #PermitRootLogin yes and change it to: PermitRootLogin no # service sshd restart

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Install and configure a Kickstart server with Cobbler on CentOS 6.4 (x86_64)

Note: Assume the Kickstart server’s IP is 192.168.1.254, DNS server is 192.168.1.253 and the IP range used for dhcp is 192.168.1.40 to 192.168.1.50. Install EPEL The EPEL RPM repository contains extra packages, such as Cobbler, for RHEL/CentOS. ==============EPEL=========http://fedoraproject.org/wiki/EPEL Run the … Continue reading

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