In Linux console, run the following command to show the public IP address of the machine. curl echoip.net ; echo
Tag: Linux
Clear Linux memory cache
There was a alert showing that the swap free space is low in a RHEL 5.6 box. I logged in and checked, the box has 13G RAM, but only 1G swap. First, this is not a good practice, as RedHat recommends 4G swap for RHEL5 with 4-16G RAM. free -m total used free shared buffers … Continue reading Clear Linux memory cache
Puppet cron job configuration
In my lab, I want everything to be controlled by puppet. So I use puppet to set up the cron job that I mentioned in step 3) in the post Integrate puppet to foreman.# Push puppet node facts to foreman*/10 * * * * /etc/puppet/push_facts.rbThe manifest can be found here as well.class sys_cron::push_facts {cron { puppet_push_facts: … Continue reading Puppet cron job configuration
Check major/ minor device number in Linux
In Linux world, everything is presented as a file in /dev to users no matter it is disk, network adapter or any other devices. In the background, kernel manages all the devices. To be specific, through the device drivers in the kernel.The devices controlled by the same device driver have a common device number which … Continue reading Check major/ minor device number in Linux
Missing NIC in cloned VirtualBox VM
If you ever encounter similar error 'Device eth0 does not seem to be present, delaying initialization' in the cloned VirtualBox VM, the fix is to remove this file (/etc/udev/rules.d/70-persistent-net.rules) and reboot the VM. The reason is that the new cloned VM generates new MAC addresses which do not match the previous ones that have been recorded … Continue reading Missing NIC in cloned VirtualBox VM
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