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Data loss will be costly. At the very least, critical data loss will have a financial impact on companies of all sizes. In some cases, it can cost your job. I’ve seen cases where sysadmins learned this in the hard way. There are several ways to backup a Linux system, including  rsync  and  rsnapshot  that we discussed a while back. This article provides 6 practical examples on using dd command to backup the Linux system. dd is a powerful UNIX utility, which is used by the Linux kernel makefiles to make boot images. It can also be used to copy data. Only superuser can execute dd command. Warning: While using dd command, if you are not careful, and if you don’t know what you are doing, you will lose your data! Example 1. Backup Entire Harddisk To backup an entire copy of a hard disk to another hard disk connected to the same system, execute the dd command as shown below. In this dd command example, the UNIX device name of the source hard disk is /dev/hda, and device name of th

Anytime Cisco releases a new IOS image for its network switch (or router), it is recommended that you upgrade it. This article explains 7 easy steps to upgrade IOS image on a cisco switch or router. Since you’ll be upgrading the IOS image, make sure you have physical access to the switch and you are in front of it. Use a console cable to connect to the switch. Please note that the steps given below will be similar to both switches and routers. However this examples shows how to upgrade ios image on a cisco catalyst switch. 1. Verify Current IOS Version After you login, go to enable mode, by entering the enable password. This example uses two cisco catalyst 3750 switches configured in stack mode as shown below. So, while upgrading you should upgrade the image on both the flash cards. # show switch Switch/Stack Mac Address : 0012.abcd.1234 H/W Current Switch# Role Mac Address Priority Version State ---------------------------

Thanks to: http://pmoghadam.com/ Adding route-map to vlan conf t interface vlan 203 ip policy route-map AT end But it is not working Cisco-3750# sh run int vlan 203 Building configuration... Current configuration : 293 bytes ! interface Vlan203 ip address 172.31.31.25 255.255.255.248 end Checking SDM (Switch Database Management) Cisco-3750# show sdm prefer The current template is "desktop default" template. Enable SDM Routing Template conf t sdm prefer routing desktop end wri mem reload Checking SDM again Cisco-3750#sh sdm prefer The current template is "desktop routing" template. Adding route-map to vlan again conf t interface vlan 203 ip policy route-map AT end Now it is working Cisco-3750#sh run int vlan 203 Building configuration... Current configuration : 317 bytes ! interface Vlan203 ip address 172.31.31.25 255.255.255.248 ip policy route-map AT end If you want to restore default sdm no sdm prefer

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