Openvswith is a virtual switch production level software, that can be used in virtual switch in VM environments like kvm , virtualbox etc.. In case of vm’s network connection to outer world is established by NAT or Bridge (Layer2 device)…
Openvswitch on fedora with kvm.
Openvswitch is the software used on both physical and virtual environments to implement L2 switching. Instalallation of openvswitch. #dnf install -y virt-install libvirt openvswitch Enabling the openvswitch service and daemon. #systemctl enable openvswitch Created symlink /etc/systemd/system/multi-user.target.wants/openvswitch.service → /usr/lib/systemd/system/openvswitch.service. #systemctl start…
kvm performance tuning.
Set swappiness to 10, swap space will be used at or 90% usage of system ram, generally on linux systems this value is 60. Checking the current swappiness value cat /proc/sys/vm/swappiness 60 To change the value at system run time…
kvm/qemu pxe boot setup on fedora.
kvm support disk less booting of operating systems over network, kvm default network can be configured to act a pxe server. packages required to setup pxe boot, tfp is a udp based file sharing service used to push the required…
netdata monitoring tool installation on fedora26
Netdata is a distributed , scalable monitoring tool available on nix , mac operating systems. net data also supports alerting with various services to send emails to users To install netdata on system , refer the git hub documentation at…
Understanding the use of /Var/Lock/Subsys on redhat systems prior to systemd.
Redhat/Centos 6 uses a upstart daemon called init , init programs has pid of 1 which sets the environment for the user, init propram after starting becomes the main parent process then executes scripts in the file /etc/rc.d/rc.sysinit then starting…
rc-local service enabling on centos7
rc-local service enabling on centos7 In redhat systemd is used as default upstart daemon replacing int, systemd provides back wards compatibility with with the init scripts, under rehdhat/centos6 id customs were supposed to run at at boot time they would…
squirrelmail Forbidden You don’t have permission to access
squirrelmail Forbidden You don’t have permission to access squirrelmail after setup when accessed shows 403 Forbidden error,this is due to improper configuration in squirrelmail.conf file. if you are using apache 2.4 version set Require all granted that should fix the…
Heroku building a simple python application.
Heroku building a simple python application. Heroku is a platfom as a service where we can build and deploy our applications, with platform as a sevice there is no need to worry about the dependencies hassles to setup environmens fot…
Scheduling disk i/o on fedora 26.
Scheduling disk i/o on fedora 26. By default on linux machines cfq i/o scheduler is used, Completely Fair Queuing (CFQ) is an I/O scheduler for the Linux kernel. cfq scheduler is generally idel and suitbale for genreal system workloads. If…