Hi Everyone,

I have an RB411U with a Sierra Aircard MC8700 in the PCI-E slot. This setup works great when it works with low latency and good speeds. The issue is that after being on for some time (usually around one week) the modem stops responding to the RB411U completely. A soft reboot of the 411U fixes the issue.

RB11U has latest version of routeros and MC8700 has latest firmware - still the same problem.

Any help would be greatly appeciated. See attached file for modem log after it stops responding:

What version of ROS?
Try 5.12 it's seems have some improvements in 3G

# Open console
/system serial-terminal usb2 channel=3

# Make diagnostic command
at+cfun?
# It should be set to
at+cfun=1
# to disable Sleep mode
# Need to power off after setting it's up

# If you modem stop responding try to do following:

/system serial-terminal usb2 channel=3
at!gstatus?

# Post the output here and make reset command
at!greset

Thank you begetan for your suggestions

It's the latest 5.12. tried running at+cfun=1 and also tried putting it in the init command. Since upgrading to RouterOS 5.12 about a month back the modem has actually been a lot worse. This modem is actually used at a clients premises so it's kind of hard to debug but I thought the combination of Sierra MC8700 + Routerboard would be extremely stable hence why I recommended it.

Attached is another log from the client which appears to be a different issue than the last. Apparently the MC8700 + Routerboard would notmake a connection where as their cheap usb modem would.

The MC8700 has proven to be an extremely well performing modem so it's a shame this setup doesn't work reliably.

Stable work of 3G card is out of interests Mikrotik team and community, I think.
I wrote a simple script that correctly restart mc8790 card if it became freezed.

Currently I'am waiting mc8705 card and probably will need the same script due to http://forum.mikrotik.com/viewtopic.php?f=3&t=58915

Thanks for your help Begetan - have read your thread and it seems to make perfect sense that that's causing it. Could you share your script that restarts the modem? (I don't really know a lot about Mikrotik) Thanks!

Thanks for your help Begetan - have read your thread and it seems to make perfect sense that that's causing it. Could you share your script that restarts the modem? (I don't really know a lot about Mikrotik) Thanks!

chiefbodge, here is my script:

http://forum.mikrotik.com/viewtopic.php ... 16#p304916

Hi, I have similar trouble with MC8775 3G PCI Card.
Continously sent +++, sent ATH.
My first doubt: why "ports=0" ???

then, after created PPP-client interface I have:

Couldn't continue - modem did not respond (6)

when I press Info... button.

at the end, if PPP-client interface disabled, I try then I haven't any answer by modem on any (0,1,2) interface.

Any ideas? Both RB411 and 3G card are new devices.
Thanks.

if the modem doesn't respond on any USB channels then you need to power cycle the board (remove the power and plug it back).
If you are able to get into the channel and apply AT command sthen try sending AT+CFUN=1,1 and usually it will reset the modem.

Already done, nothng changed. Like if communication to modem would be disabled.

it's an old never solved problem

PLEASE FIX DRIVER PROBLEM

Thanks

it's an old never solved problem
PLEASE FIX DRIVER PROBLEM

Do you mean about MC8775 or MC8700?

Sierra MC8700.

Works very good about performance BUT after 40/60 hours you loose activity from mc8700-port-routerboard. It goes on "resetting link".

You can make 200 soft reboot but you don't solve the problem. If you POWEROFF then poweron, it start works fine again for other 40/60 hours.

Strange thing: if you DON'T poweroff and wait, after 10/15 hours of soft reboot (watchdog) it starts work again. Why?

Similar problem with huawey EM820U. With Sierra EU850D no problem, online since 5 month, but the performance are very very poor (of EU850D)

I just received two Huawei EM820w modems. Setup was easy. Testing is started. I will get back to you in a few days with an update. Mainly i use the combination of RB411U and Novatel EU870D for SCADA and Telemetry and it performs well but since is an old modem the link speed will not pass over 2mbps even with the firmware update. The Huawei EM820w was able to reach out of the box 8.5mbps download and almost 1mbps upload and i don't have HSUPA+ coverage in this area. I will re-test in an area with HSUPA+ coverage.

Same problem with MC8775.
See my post: RB411U+Sierra Wireless 8775=freez dialing out.. or dialing..
http://forum.mikrotik.com/viewtopic.php?f=2&t=66307

I'm using this logical step:

AT+CFUN=1,1
if connection is still ko then AT!GRESET

if connection is still ko then DISABLE PPP - REBOOT SW + ENABLE PPP

if connection is still ko then REBOOT HW

Hi ibm390s,

could you tell me if you had to go through any special steps to get the Huawei em820w to work. I tried RouterOS 5.22 and 6.0rc4, neither detected the USB device. Also upgraded my firmware 3.0. The board simply doesn't detect the modem - I just want to be sure it's not a software/driver issue before I go through the motion of RMA'ing my modem.

Thanks!

Mainly i use the combination of RB411U and Novatel EU870D

Do you mean EU870D, mainly used for DELL 5520 laptops?
I've bought one (sold as 5520 modem, but in fact it's an EU870D).
I have 2 channels, but one is not responding. If I use AT commands to reset or to set link mode (3G, EDGE, and so on), it responds with "ERROR".
I can't neither use AT+CFUN command.
After about 40 hours USB resources doesn't detect modem, so I need a power-off restart.
Is this a known bug of Routeros or about modem?
Is there a way to update the firmware of the modem directly form RB411U?

@MTFan

No special procedure needed. Just inserted the card in the slot, secured with the two screws, powered the RB411U and the modem was detected by the OS and drivers were loaded.

@el berto

Yes, indeed i'm using those modems from Dell laptops. Connected them to my laptop using a USB adapter. These are the screens with the modem specs. To be able to update the modem firmware you should remove it from the RB and hook it up to either a laptop with SIM slot or to a USB adapter with SIM slot.

This is the daily chart for a RB411U + EU870D which i test right now. Fixed IP from the carrier (vodafone) testing with ping from The Dude. Stable over the last 30 hours. After reaching at least 6-7 days of uptime for the link i will start to test the Huawey modems.

Connected them to my laptop using a USB adapter.

Do you really have miniPCI-e (socket) to usb (plug) adapter?
Never seen before, could you give me model?
Thanks.

Here it is.

Consider that the modem interface is USB not mini pci-e. for example, the EU850 which has onboard SIM support can be used in any laptop even without SIM socket. But the interface on the laptop should support USB devices also.

Hey!

Did you manage to test the Huawei hardware?
How did it perform?

MAtej