I am following openflow tutorial on openflow tutorial. I am using mininet and ryu controller and openvswitch version 2.8.0. When I try to use command:
sudo ovs-ofctl show s1
It gives error as below:
asd@asd:~/ryu/ryu/mpls$ sudo ovs-ofctl show s1
ovs-ofctl: /var/run/openvswitch/s1.mgmt: failed to open socket (Connection refused)
As I am using sudo, I think there should not be any problem regarding permissions for opening socket connection. Not sure what is causing this error. Help is appreciated.
The error message is saying that ovs-vswitchd did not open the Unix socket expected at /var/run/openvswitch/s1.mgmt. This usually means that ovs-vswitchd (the daemon process for Open vSwitch) is not running.
You can check that by running:
$ ps aux | grep ovs-vswitchd
root 77289 0.0 0.0 25632 4916 ? Ss 16:05 0:00 ovsdb-server --remote=punix:/var/run/openvswitch/db.sock --remote=db:Open_vSwitch,Open_vSwitch,manager_options --private-key=db:Open_vSwitch,SSL,private_key --certificate=db:Open_vSwitch,SSL,certificate --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert --log-file=/var/log/openvswitch/ovs-vswitchd.log -vsyslog:info -vfile:info --pidfile --detach
root 77295 100 0.2 2608140 45820 ? Ssl 16:05 3:13 ovs-vswitchd unix:/var/run/openvswitch/db.sock --pidfile --detach --log-file=/var/log/openvswitch/ovs-vswitchd.log -vfile:info
paul 77447 0.0 0.0 14228 968 pts/2 S+ 16:08 0:00 grep --color=auto ovs-vswitchd
The first process, ovsdb-server, answers to OVSDB queries. The second process, ovs-vswitchd, answers to OpenFlow queries and processes packets.