Starting with Contrail Networking Release 2008, Sandump tool is available in
contrail-tools container. You can use the Sandump tool on macOS machines.
Sandump tool captures the Sandesh messages from netlink connection between Agent and
vRouter (only DPDK mode) and provides interpretation of all the captured bytes.
Starting with Contrail Networking Release 2011, you can use Sandump tool on
Windows machines.
Sandesh is a southbound interface protocol based on Apache Thrift, to send analytics
data such as system logs, object logs, UVEs, flow logs, and the like, to the
collector service in the Contrail Insights node.
You can analyze the captured bytes in Wireshark. The Wireshark plugin parses the hex
dumps of all Sandesh objects. You must use Wireshark Release 3.2 and later.
You must have Wireshark application installed on your machine. You can download
Wireshark from the Download Wireshark page.
For more details on Wireshark, see https://www.wireshark.org/docs/.
Follow the procedure to use Sandump tool:
-
Run the
sandump
command. It gives summary of each message
which is being transferred between the agent and the vRouter.
(vrouter-agent-dpdk)[root]$ ./sandump -h
Sandump - Sandesh dump utility
Usage:
./sandump -w <filename> [filename to write the sandesh packets]
./sandump -c <filename> [force cleanup]
(vrouter-agent-dpdk)[root]$
-
Copy the output into a file.
(vrouter-agent-dpdk)[root]$ ./sandump -w <filename>.pcap
Dumping into <filename>.pcap
Running as user "root" and group "root". This could be dangerous.
Capturing on 'lo'
12 ^C
./sandump: closing...
(vrouter-agent-dpdk)[root]$
The command generates a file which contains sniffed bytes converted in to the
pcap format.
-
Analyze the captured packets transferred between the agent and the
vRouter.
(vrouter-agent-dpdk)[root]$ ./sandump
Running as user "root" and group "root". This could be dangerous.
Capturing on 'lo'
1 2020-08-04 09:51:01.233639252 Agent → Vrouter Vif 790 Operation: Dump Type: Host ID: 0
2 2020-08-04 09:51:01.251279611 Vrouter → Agent Response, Vif 3966 Response: 0x0000000, Multiple vr_interface_req
3 2020-08-04 09:51:33.290323560 Agent → Vrouter Mem Stats 869 Operation: Get
4 2020-08-04 09:51:33.290964111 Vrouter → Agent Response, Mem Stats 899 Response: 0x00000000
5 2020-08-04 09:51:46.175797696 Agent → Vrouter Info 137 ID: 0 Operation: Dump
6 2020-08-04 09:51:46.176494123 Vrouter → Agent Response, Info 1949 Response: 0x00000001 ID: 0
7 2020-08-04 09:51:58.920197081 Agent → Vrouter Nexthop 280 Nexthop ID: 0 Operation: Dump
8 2020-08-04 09:51:58.920905495 Vrouter → Agent Response, Nexthop 3898 Response: 0x4000001, Multiple vr_nexthop_req
9 2020-08-04 09:51:58.922297667 Agent → Vrouter Nexthop 280 Nexthop ID: 0 Operation: Dump
10 2020-08-04 09:51:58.922425514 Vrouter → Agent Response, Nexthop 3930 Response: 0x4000001, Multiple vr_nexthop_req
11 2020-08-04 09:51:58.923525453 Agent → Vrouter Nexthop 280 Nexthop ID: 0 Operation: Dump
12 2020-08-04 09:51:58.926925821 Vrouter → Agent Response, Nexthop 792 Response: 0x0000000, Multiple vr_nexthop_req
^C12 packets captured
./sandump: closing...
(vrouter-agent-dpdk)[root]$
-
Analyze the pcap file in WireShark.