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Category Archives: Virtualization

KVM ubuntu guest console not working

On KVM Virtual Machine running Ubuntu Guest, console command shows blank screen. This is because serial console is not running in Ubuntu Guest. Connect to guest using VNC. Create file Add following content The content of the file is Now,


virsh error: Unable to create cgroup for x: No such file or directory

I have 2 test KVM virtual machine on a server Recently i tried start one of the Virtual Machine, i got following error. After some searching, i found this is due to bug in “systemd”, that deletes cgroup directory that


Docker

Installing Docker Ubuntu 16.04 CentOS 7 CentOS 6 Debian 9 Working with Docker Dockerfile docker run docker commit – Creating your own custom image with Docker docker compose baseimage-docker Remove all docker containers Entering Running Docker Container Docker Tricks Find


OpenVZ VPS Creation Error – The ploop image can not be used on ext3 or ext4

When i create a VPS, i got error This is because OpenVZ recently started using ploop image for OpenVZ virtual machines. To fix this, edit /etc/vz/vz.conf Find Replace With Now you will be able to create VPS.


Installing CSF in OpenVZ Hardware Node

If you install CSF on OpenVZ hardware node, you won’t be able to access VPS. To fix this create a file /etc/csf/csfpre.sh with following content [root@server12 ~]# cat /etc/csf/csfpre.sh /sbin/iptables -A INPUT -i venet0 -j ACCEPT /sbin/iptables -A OUTPUT -o


Install VNC Server on CentOS

First install vncserver as user root yum install vnc-server I wanted VNC run as user “flashwebhost” as it is not recommended to use Desktop as user root, so i created a user adduser flashwebhost Now setup VNC Password for this


OpenVZ BC proc entries

To see resource usage on all VPS, run one of the following commands on Node. cat /proc/user_beancounters cat /proc/bc/resources To see iostat [root@server12 233]# cat /proc/bc/iostat sda 233 I 0 0 1 0 19 1 8 sda 222 I 0


OpenVZ Commands

To start a VPS vzctl start <VPSID> To Stop a VPS vzctl stop <VPSID> To Restart a VPS vzctl restart <VPSID> To Delete a VPS (all data will be deleted, no confirmation, so be careful) vzctl destroy <VPSID> To show


Show All OpenVZ Virtual Machines On A Server

vzlist shows all virtual machines on a server To get currently running VPS, run vzlist [root@server12 ~]# vzlist CTID NPROC STATUS IP_ADDR HOSTNAME 244 27 running 174.36.130.247 sam.localhost [root@server12 ~]# To get all VPS on the server, run vzlist -a


OpenVZ ubuntu guest have not networking

I created an OpenVZ vps with ubuntu template ubuntu-9.10-x86.tar.gz After login to VPS, there was no networking enabled in the VPS root@server70 [/vz/template/cache]# vzctl enter 102 entered into CT 102 root@hosthat:/# ifconfig root@hosthat:/# ping yahoo.com ping: unknown host yahoo.com root@hosthat:/#