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    <font color="#804000">I'm using a Quectel EC21 modem on a Debian
      Buster Linux system (using modemmanager 1.10.0).<br>
      <br>
      I want to force it to one of 3G or 4G to stop it changing/swapping
      between the two.<br>
      <br>
      I've tried using the `mmcli -m 0 --set-allowed-modes=3g<br>
      `.  mmcli seems happy with that.<br>
      <br>
    </font>
    <blockquote><font color="#804000"><tt># mmcli -m 0</tt><br>
        <tt>  --------------------------------</tt><br>
        <tt>  Modes    |            supported: allowed: 3g; preferred:
          none</tt><br>
        <tt>           |                       allowed: 4g; preferred:
          none</tt><br>
        <tt>           |                       allowed: 3g, 4g;
          preferred: 3g</tt><br>
        <tt>           |                       allowed: 3g, 4g;
          preferred: 4g</tt><br>
        <tt>           |              current: <b>allowed: 3g;
            preferred: none</b></tt><br>
        <tt>  --------------------------------</tt><br>
      </font></blockquote>
    <font color="#804000"><br>
      and the modem connects using 3G (umts).<br>
      <br>
    </font>
    <blockquote><font color="#804000"><tt> 
          --------------------------------</tt><tt><br>
        </tt><tt>  Status   |                 lock: sim-pin2</tt><tt><br>
        </tt><tt>           |       unlock retries: sim-pin (3),
          sim-pin2 (3), sim-puk (10), sim-puk2 (10)</tt><tt><br>
        </tt><tt>           |                state: connected</tt><tt><br>
        </tt><tt>           |          power state: on</tt><tt><br>
        </tt><tt>           |          access tech: <b>umts</b></tt><tt><br>
        </tt><tt>           |       signal quality: 57% (recent)</tt><tt><br>
        </tt><tt>  --------------------------------</tt><tt><br>
        </tt></font></blockquote>
    <font color="#804000"><br>
      However, some time later it swaps over to 4G (lte)<br>
      <br>
    </font>
    <blockquote><font color="#804000"><tt> 
          --------------------------------</tt><tt><br>
        </tt><tt>  Status   |                 lock: sim-pin2</tt><tt><br>
        </tt><tt>           |       unlock retries: sim-pin (3),
          sim-pin2 (3), sim-puk (10), sim-puk2 (10)</tt><tt><br>
        </tt><tt>           |                state: connected</tt><tt><br>
        </tt><tt>           |          power state: on</tt><tt><br>
        </tt><tt>           |          access tech: <b>lte   
            <<< 4G !!!</b></tt><tt><br>
        </tt><tt>           |       signal quality: 63% (recent)</tt><tt><br>
        </tt><tt>  --------------------------------</tt><tt><br>
        </tt></font></blockquote>
    <font color="#804000"><br>
      Have I got the right expectations of the `--set-allowable-modes`
      feature?<br>
      <br>
      Is there something else I need to do?<br>
      <br>
      Does this feature work with MM 1.10.0 ?<br>
      I did see some forum discussions about it not working and also
      patches, but I can't quite figure out whether that was pre or post
      v1.10.0.<br>
      <br>
      There is a backport of MM 1.14.0 which I could try.  Is a later
      version likely to help?<br>
      <br>
      The MM changelog/news file doesn't seem to suggest there is an
      issue or fix.<br>
      <br>
      I did find this in the git commits, but not sure if it is relevant
      or not.<br>
      <br>
    </font>
    <blockquote>
      <div class="commit-subject"><font color="#804000"><b>policy: Use
            SetCurrentModes instead of SetAllowedModes<br>
            <br>
          </b></font></div>
      <div class="commit-msg"><font color="#804000">There is no DBus API
          for SetAllowedModes, but only for SetCurrentModes.
          (cherry picked from commit <a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/commit/?id=e21e7ddfae3d68418ad9c6f4d589b720b7b85b8b">e21e7ddfae3d68418ad9c6f4d589b720b7b85b8b</a>)<br>
          <br>
        </font></div>
    </blockquote>
    <blockquote>
      <table summary="commit info" class="commit-info">
        <tbody>
          <tr>
            <th><font color="#804000">author</font></th>
            <td><font color="#804000">Mohammed Sadiq
                <a class="moz-txt-link-rfc2396E" href="mailto:sadiq@sadiqpk.org"><sadiq@sadiqpk.org></a></font></td>
            <td class="right"><font color="#804000">2019-09-24 19:10:29
                +0530</font></td>
          </tr>
          <tr>
            <th><font color="#804000">committer</font></th>
            <td><font color="#804000">Aleksander Morgado
                <a class="moz-txt-link-rfc2396E" href="mailto:aleksander@aleksander.es"><aleksander@aleksander.es></a></font></td>
            <td class="right"><font color="#804000">2019-09-25 13:38:50
                +0200</font></td>
          </tr>
          <tr>
            <th><font color="#804000">commit</font></th>
            <td colspan="2" class="sha1"><font color="#804000"><a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/commit/?h=mm-1-10&id=b34203b1b8e8676bb686f0c33ba3104c8577b855">b34203b1b8e8676bb686f0c33ba3104c8577b855</a>
                (<a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/patch/?id=b34203b1b8e8676bb686f0c33ba3104c8577b855">patch</a>)</font></td>
          </tr>
          <tr>
            <th><font color="#804000">tree</font></th>
            <td colspan="2" class="sha1"><font color="#804000"><a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/tree/?h=mm-1-10&id=b34203b1b8e8676bb686f0c33ba3104c8577b855">80a501b5eae527399c783a2c09e84e1d5b86fe02</a></font></td>
          </tr>
          <tr>
            <th><font color="#804000">parent</font></th>
            <td colspan="2" class="sha1"><font color="#804000"><a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/commit/?h=mm-1-10&id=00c0911cb2e0e4558d98f4fe5085cd2be89f9ec3">00c0911cb2e0e4558d98f4fe5085cd2be89f9ec3</a>
                (<a
href="https://cgit.freedesktop.org/ModemManager/ModemManager/diff/?h=mm-1-10&id=b34203b1b8e8676bb686f0c33ba3104c8577b855&id2=00c0911cb2e0e4558d98f4fe5085cd2be89f9ec3">diff</a>)</font></td>
          </tr>
        </tbody>
      </table>
    </blockquote>
    <font color="#804000"><br>
      <br>
      Thanks,<br>
      Brendan.<br>
      <br>
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