Hi Jonas, On 8/18/19, Jonas Bonn wrote: >>> OK, all from kernel, what could make the kernel to delete the link? > > What does the kernel log show? ....... kernel: qmi_wwan 1-1:1.3: nonzero urb status received: -71 kernel: qmi_wwan 1-1:1.3: wdm_int_callback - 0 bytes kernel: qmi_wwan 1-1:1.3: wdm_int_callback - usb_submit_urb failed with result -19 kernel: qmi_wwan 1-1:1.3 wwan0: unregister 'qmi_wwan' usb-ci_hdrc.1-1, WWAN/QMI device ...... Attached full kernel log file. The test device is currently in link down and connected to WiFi. > It looks like you've multiple instances of connman and ofono running > there, that's why you've got nothing in the logs. Give this another try. Hmm, don't think so: # ps | grep connman | grep -v grep 3465 root 8948 S connmand -d # ps | grep ofono | grep -v grep 319 root 5656 S ofonod -d # systemctl status connman Active: inactive # systemctl status ofono Active: inactive # kill 3465 # ps | grep connman | grep -v grep # kill 319 # ps | grep ofono | grep -v grep # OFONO_QMI_DEBUG=1 ofonod -d # connmand -d # ps | grep connman | grep -v grep 4912 root 8944 S connmand -d # ps | grep ofono | grep -v grep 4910 root 5712 S ofonod -d # journalctl -u ofono > ofono.log # journalctl -u connman > connman.log same contexts in the log files, what I could be missing? Thanks Jonas - jh