How to analyze the interactive data between openvswitch ovs-vsctl commands and ovsdb-server
This article is about how to analyze the interactive data between openvswitch ovs-vsctl commands and ovsdb-server. The editor thinks it is very practical, so I share it with you. I hope you can get something after reading this article.
Use strace to analyze ovs-vsctl commands system call
Strace ovs-vsctl list-br
Some of the output is as follows, so ovs-vsctl communicates with ovsdb-server through unix socker (/ var/run/openvswitch/db.sock)
Socket (AF_UNIX, SOCK_STREAM, 0)
Connect (3, {sa_family=AF_UNIX, sun_path= "/ var/run/openvswitch/db.sock"}, 31) = 0
How to monitor unix socket communication data
No information was found for "monitoring unix socket communication data through tcpdump".
The following describes how to monitor unix socket communication data through socat.
1. Start socat
Socat-T100-v UNIX-LISTEN:/tmp/duplicatesocket,mode=777,reuseaddr,fork UNIX-CONNECT:/var/run/openvswitch/db.sock
two。 When you execute the ovs-vsctl command, set the-- db parameter
Ovs-vsctl-db unix:/tmp/duplicatesocket list-br
Socat output part of the result
> 2017-04-26 10 method 04method 24.271932 length=56 from=0 to=55 {"id": 0, "method": "get_schema", "params": ["Open_vSwitch"]} < 2017-04-26 10purl 04vis24.273208 length=8192 from=0 to=8191 {"id": 0, "result": {"cksum": "2211824403 22535", "name": "Open_vSwitch", "version": "7.12.1" "tables": {"Controller": {"columns": {"connection_mode": {"min": 0, "key": {"type": "string", "enum": ["set", ["in-band", "out-of-band"]}, "is_connected": {"ephemeral": true, "type": "boolean"}, "local_gateway": {"type": {"min": 0, "key": "string"}} "enable_async_messages": {"type": {"min": 0, "key": "boolean"}}, "external_ids": {"type": {"max": "unlimited", "min": 0, "key": "string", "value": "string"}}, "other_config": {"type": {"max": "unlimited", "min": 0, "key": "string", "value": "string"}}, "status": {"ephemeral": true "type": {"max": "unlimited", "min": 0, "key": "string", "value": "string"}}, "local_netmask": {"type": {"min": 0, "key": "string"}}, "controller_burst_limit": {"type": {"min": 0, "key": {"minInteger": 25, "type": "integer"}}, "local_ip": {"type": {"min": 0 "key": "string"}}, "controller_rate_l above is how to analyze the interactive data between openvswitch ovs-vsctl commands and ovsdb-server. The editor believes that there are some knowledge points that we may see or use in our daily work. I hope you can learn more from this article. For more details, please follow the industry information channel.
