I observe that by default only eth0 can get IP address from DHCP
For eth1, IP is an APIPA address, as below:
1. For the same type of ethernet interfaces, does connman only maintain
one interface, like eth0?
No, internally ConnMan is tracking all interfaces (unless blacklisted).
The D-Bus API does not export device infos. So you only see Services
which map to different interfaces.
2. Shall I use session API to enable another interface, like eth1?
create another route table for eth1?
Should not be needed but it probably would work.
3. If yes, where can I find the user guide to use session API?
There is only our doc folder which contains all the written down
information. Not really much I know :/