Saving iptables rules: iptables: Saving firewall rules to /etc/sysconfig/iptables: /etc/init.d/iptables: line 268: restorecon: command not found [FAILED] This error mainly occurs due to misisng restorecon file. restorecon is provided by policycoreutils package. You can try uninstalling and re-installing policycoreutils package and see if you get restorecon file under /sbin Installing policycoreutils package: root@server [~]# yum …

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ip_conntrack is an iptables module which limits number of simultaneous connections your system can have. If this connections are exceed, then your server may not respond to  ping and ssh. by default a linux Cent OS server have 65536 connection.   Today I faced same issue with my server.  and Fixed for the same was increasing the …

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Change timezone on CentOS If you have CentOS/RHEL Server then you can fallow following steps: 1) SSH the server as root. All Time zone configuration files are located under directory /usr/share/zoneinfo/ Example: Say your current server time is in GMT Format and you want to change it to IST time. cp /usr/share/zoneinfo/Asia/Calcutta     /etc/localtime Thats all   …

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Wine is a free software application that aims to allow computer programs written for Microsoft Windows to run on Unix-like  operating systems. Wine also provides a software library, known as Winelib, against which developers can compile  Windows applications to help port them to Unix-like systems. SSH the server as root and refer to following steps …

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Booting UBUNTU into single user mode is slightly different then CENTOS. 1) Hold the Shift key at boot to display the Grub boot menu. If you fail to press Shift key then you will not see boot menu 2) Select the first Grub entry, it will be similar to: Ubuntu, with Linux 2.6.32-22-generic-pae 3) Press e to edit the the …

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