Miscelanious Linux and OpenStack Notes
Miscelanious Linux and OpenStack Notes
Linux Networking Notes
Handy options for tcpdump:
tcpdump -nlei $interface
Check on the status of HAProxy:
echo "show info;show stat;show table" | socat /var/lib/haproxy/stats stdio
Pretty ip link details and statistics output:
ip -s -d -o link | sed G | tr '\\' '\n'
Check what Interface pairs up with a veth interface:
ethtool -S $vethDevice
This ID will match up with the entry number in the output of ip link or ip addr
An example of using this to match up a veth interface in a namespace to its corresponding veth interface in another namespace:
root@node-1:~# ip netns exec haproxy ip -d link show dev b_public
36: b_public: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
link/ether 32:cc:0c:f3:ea:34 brd ff:ff:ff:ff:ff:ff promiscuity 0
veth
root@node-1:~# ip netns exec haproxy ethtool -S b_public
NIC statistics:
peer_ifindex: 37
root@node-1:~# ip -o -d link | grep "^37"
37: v_public: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br-ex state UP mode DEFAULT group default qlen 1000\ link/ether d2:06:96:a4:39:18 brd ff:ff:ff:ff:ff:ff promiscuity 1 \ veth
root@node-1:~#
List all Network Namespaces without using the ip command:
ls /var/run/netns
Find the Inode of a process’s Network Namespace:
readlink /proc/{0..9}*/ns/net | sort | uniq
Find the Inode of a Network Namespace:
stat /var/run/netns/*
OpenStack Networking Notes
Quickly find what router is associated with a Network from the DB
I have yet to find a quick way to identify which Neutron Router is associated with a given Neutron Network ID, so I’ve assembled the following query to speed up this process:
SELECT router_id,port_id,network_id FROM ports t1 INNER JOIN routerports t2 ON t1.id = t2.port_id where network_id="NETWORK_UUID";
This query can easily be called in bash with the following function:
network_to_router() { mysql neutron -e "SELECT router_id,port_id,network_id FROM ports t1 INNER JOIN routerports t2 ON t1.id = t2.port_id where network_id=\"$1\";" ; }