root@OpenWrt:~# quectel-CM -s cmnet -4 -6
[04-14_06:56:51:778] Quectel_QConnectManager_Linux_V1.6.0.25
[04-14_06:56:51:779] network interface '' or qmidev '' is not exist
[04-14_06:56:51:780] netcard driver = pcie_mhi, driver version = V1.3.0.17
[04-14_06:56:51:781] qmap_mode = 4, qmap_version = 9, qmap_size = 16384, muxid = 0x81, qmap_netcard = rmnet_mhi0.1
[04-14_06:56:51:782] Modem works in QMI mode
[04-14_06:56:51:783] connect to quectel-qmi-proxy0 sockfd = 7
[04-14_06:56:51:783] cdc_wdm_fd = 7
[04-14_06:56:51:789] Get clientWDS = 15
[04-14_06:56:51:792] Get clientWDS = 16
[04-14_06:56:51:794] Get clientDMS = 3
[04-14_06:56:51:798] Get clientNAS = 4
[04-14_06:56:51:801] Get clientUIM = 1
[04-14_06:56:51:805] Get clientWDA = 1
[04-14_06:56:51:809] requestBaseBandVersion RM500QGLABR10A03M4G
[04-14_06:56:51:813] qmap_settings.rx_urb_size = 16384
[04-14_06:56:51:813] qmap_settings.ul_data_aggregation_max_datagrams  = 11
[04-14_06:56:51:814] qmap_settings.ul_data_aggregation_max_size       = 8192
[04-14_06:56:51:814] qmap_settings.dl_minimum_padding                 = 0
[04-14_06:56:51:835] requestGetSIMStatus SIMStatus: SIM_READY
[04-14_06:56:51:836] requestSetProfile[1] cmnet///0
[04-14_06:56:51:848] requestGetProfile[1] cmnet///0
[04-14_06:56:51:852] requestRegistrationState2 MCC: 460, MNC: 0, PS: Attached, DataCap: 5G_NSA
[04-14_06:56:51:857] requestQueryDataCall IPv4ConnectionStatus: DISCONNECTED
[04-14_06:56:51:860] requestQueryDataCall IPv6ConnectionStatus: DISCONNECTED
[04-14_06:56:51:861] ifconfig rmnet_mhi0 down
[04-14_06:56:51:885] ifconfig rmnet_mhi0.1 0.0.0.0
ifconfig: SIOCSIFFLAGS: Network is down
[04-14_06:56:51:909] ifconfig rmnet_mhi0.1 down
[04-14_06:56:51:943] requestSetupDataCall WdsConnectionIPv4Handle: 0x341450a0
[04-14_06:56:52:423] requestSetupDataCall WdsConnectionIPv6Handle: 0x341439f0
[ 1001.561353] net rmnet_mhi0: link_state 0x0 -> 0x1
[04-14_06:56:52:441] ifconfig rmnet_mhi0 up
[ 1001.584623] [I][mhi_netdev_open] Opened net dev interface
[04-14_06:56:52:467] ifconfig rmnet_mhi0.1 up
[04-14_06:56:52:495] you are use OpenWrt?
[04-14_06:56:52:496] should not calling udhcpc manually?
[04-14_06:56:52:496] should modify /etc/config/network as below?
[04-14_06:56:52:497] config interface wan
[04-14_06:56:52:497] 	option ifname	rmnet_mhi0.1
[04-14_06:56:52:497] 	option proto	dhcp
[04-14_06:56:52:498] should use "/sbin/ifstaus wan" to check rmnet_mhi0.1 's status?
[04-14_06:56:52:498] busybox udhcpc -f -n -q -t 5 -i rmnet_mhi0.1
udhcpc: started, v1.28.3
udhcpc: sending discover
udhcpc: sending select for 10.245.22.3
udhcpc: lease of 10.245.22.3 obtained, lease time 7200
[04-14_06:56:52:713] udhcpc: ifconfig rmnet_mhi0.1 10.245.22.3 netmask 255.255.255.248 broadcast +
[04-14_06:56:52:754] udhcpc: setting default routers: 10.245.22.4
[04-14_06:56:52:838] ip -6 address flush dev rmnet_mhi0.1
[04-14_06:56:52:861] ip -6 address add 2409:8930:463:3daa:7c8e:429a:c902:c6cc/64 dev rmnet_mhi0.1
[04-14_06:56:52:884] ip -6 route add default dev rmnet_mhi0.1

root@OpenWrt:~# cat /etc/resolv.conf 
nameserver 2409:8030:2000:0:0:0:0:1 # IPV6 rmnet_mhi0.1
nameserver 2409:8030:2000:0:0:0:0:2 # IPV6 rmnet_mhi0.1
search lan
nameserver 127.0.0.1

root@OpenWrt:~# ip -6 ro show
2409:8930:463:96df::/64 dev rmnet_mhi0.1  proto kernel  metric 256 
fe80::/64 dev br-lan  proto kernel  metric 256 
fe80::/64 dev br0  proto kernel  metric 256 
default dev rmnet_mhi0.1  metric 1024 

root@OpenWrt:~# ping6 www.qq.com
PING www.qq.com (2402:4e00:1430:1301::9227:79cc:76f2): 56 data bytes
64 bytes from 2402:4e00:1430:1301::9227:79cc:76f2: seq=0 ttl=51 time=97.230 ms
