Using u-blox TOBY-R200, ModemManager not detecting already registered with network

Matthew Starr mstarr at
Thu Feb 8 14:25:00 UTC 2018


Unfortunately changing the settings does not resolve the exact issue I have.  The issue I have is that ModemManager is not waiting for the TOBY R200 modem to auto register itself and instead is telling the modem to reregister with the network right before the modem finishes its auto registration.  This causes the modem to take about 70-90 seconds to reregister with the network.  The default number of retries to get the connection to complete seems to be fine in my situation as I only see NetworkManager try once to connect and it eventually connects after the delay caused by ModemManager.

Best regards,
Matthew Starr

> -----Original Message-----
> From: Aleksander Morgado [mailto:aleksander at]
> Sent: Wednesday, February 07, 2018 2:01 PM
> To: Matthew Starr
> Cc: Dan Williams; modemmanager-devel at
> Subject: Re: Using u-blox TOBY-R200, ModemManager not detecting already
> registered with network
> >
> > There is still an issue that exists where if the GSM connection in
> NetworkManager is setup for "connection.autoconnect yes".  At boot it the
> GSM connection now takes 70-90 seconds to connect after the start of trying,
> which is 1.5 to 2 times as long as it used to be.  It looks like NetworkManager
> is requesting the connection up before the initial modem registration on
> the network and this is causing the delay that was seen always before your
> patch.  Is there any way to force NetworkManager to wait for just the GSM
> connection or to have ModemManager wait for auto registration before
> continuing with the Registration step?
> I may have seen this just yesterday myself doing some tests. I got a quick
> workaround just by letting NetworkManager retry indefinitely until a
> connection was done, with "autoconnect-retries=0" (in addition to
> autoconnect=true). Otherwise, NM was trying 3 or 4 quick attempts, all
> failing, and then it would wait a long time before retrying again, which is
> when it succeeded.
> That said, this is something to fix somewhere in MM or NM. The connection
> attempt using Simple.Connect() as NM does should wait for the modem to
> get fully enabled and registered, it shouldn't blindly error out quickly, which
> is what I believe it was doing.
> --
> Aleksander

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