RB750UP + 3G USB = freezes completely

Hardware MikroTik hardware general
21

5.13 did not fix it… :frowning:

22

remezen

I’ve got stupid Megafon too :slight_smile: But on completely different configuration RB411UAHR and PCI-e modem Sierra Wireles.
I found that all “freezing” problem is due to incorrect handling of 3G modem errors by ROS.

Mikrotik sent ATH command if caught en error in connection.
Modern 3G Modem do nothing when recieve ATH command, just reply OK.

For huawei modems works AT+CHUP

For Siera Wireless nor ATH, or AT+CHUP works, only AT!GRESET actualy restart connection, and sometimes interface enable only can helps.

Here is my script for check and restart 3G modem

/system script
add name=ppp-restart source=":local iface;\r\
    \n:foreach i in=[/interface find type=\"ppp-out\"]  do={\r\
    \n    :set iface [/interface get \$i name];\r\
    \n    /interface ppp-client monitor \$i once do={\r\
    \n        :if (\$status!=\"connected\") do={  \r\
    \n            /interface disable \$iface;\r\
    \n            :delay 5s;\r\
    \n            :log info \"ppp-watch status: \$status,  restarted: \$iface\";\r\
    \n            /interface enable  \$iface;\r\
    \n           }\r\
    \n    :log info \"ppp-watch status: \$status\";  \r\
    \n    }\r\
    \n}\r\
    \n"
23

I’ve had a similar problem for the first time with my RB750UP and 3G modem. All the Ethernet LEDs were out so I had no connectivity to the device and had to power cycle it. It’s been running for a couple of months without issue before this.

No supout.rif file created automatically so I’ve generated one and sent to support.


Matt.

24

Same problem with my RB751G when using 3G modem. But router not hang completely some function disappears, interface table is empty. Reboot, shutdown commands don’t work. Only recycle power helped. I notice that problem occur when signal of modem is weak or lost.

25

could you check the datasheet of the usb modem, what is the power consumption for 3g and for 2g?
On the RB751G, does it happen the same problem if you disable the wireless interface on RB751G and use that 3g modem?

26

Hmm, Yes, it happen frequently when i increase TX power to 25dbm. I shall try to find spec. I found the same problem if i connect with large usb cable to 3g, it always hang instantly, need to reconnect power to bring in working condition. I have maked supout.rif if needed…

27

The best information I can find on the 3G modem I have (ZTE MF626) is that it draws 100mA idle and maximum of 450mA however it doesn’t break it down between 2G and 3G.

http://www.3gmodem.com.hk/ZTE/MF626.html


Matt.

28

I sure it is not power issue, i upgraded latest, and checkout “dial on demand” from PPP tab. Now if 3g signal lost, router not hang any more, but couldnot connect to modem, need to reconnect usb to work again.

29

Very boring ,see all the connections are connected ,but it is very very slow to open the web page :frowning:

30

hope this will help you http://www.wifitech.com.pk/howto-connect-evonitro3g-modem-with-mikrotik/

31

I’ve got the exact same issue with 3 of my RB750UP’s, did anyone managed to fix this issue?

I’ve tested it on all versions of ros, no luck… the stuff is unstable

and I’m using K3772-Z dongles

32

I had the same problem with 750UP and 3G modem. Does anyone find any solution or justification to this strange behavior? My 750UP put all leds on and lost any eth connection, but I lost it completely!
It doesn’t restart with power cycle; always all leds on and no eth connection!
I’m able to do netinstall with success. However, when rebooting after netinstall, router returns in previous state (all leds lit and no eth). :frowning: