Question

Hi.  I have a RUT950 running RUT9_R_00.07.01.2 in the U.S.  I have two SIMs, ATT and T-Mobile.  I am only able to get one of the two SIMs to work at any given time and it appears to be that SIM slot 1 is the only SIM to work when attempting to get both going.  I have been able to get both SIMs to work in SIM slot 2 or in SIM slot 1 but not when I'm trying to set up both SIMs at the same time.  The goal is to have both SIMs in the modem and either automatically flip between them or manually do that.  Problem is I can only get one to work at a time.

Something weird happens where the APN settings for the SIMs seem to be linked.  If I start changing APN settings for one SIM I get an error message stating I can't have the same SIM assigned to two interfaces.  It was changing the SIM selection from SIM 2 to SIM 1 and since I'm already using SIM 1 on a different interface it gave a conflict error.  Disabling interfaces and then making changes seems to help the situation but the end result is still the same.  I can only get one to work at a time.  For the most part one SIM works and I can't get the other SIM to work no matter what.  It would likely require a SIM swap and start over.  For the SIM that is not working I get signal and everything comes up including an IP address on the interface.  The only thing that doesn't work - Data Connection State = Disconnected.  

I reverted to older software.  No difference.  Thanks for any pointers.

Answer 1

Hello,

If I understood your question correctly you'd like to have both SIM cards connected to their designated operators at the same time with data connection. The only product that can currently run 2 SIM cards simultaneously at the same time with data connection is the RUTX12 since it has 2 separate modems - one modem for one SIM card.

Every other product with 2 SIM card slots will connect to the operator using the default SIM card and, in case the primary connection goes down, the secondary SIM card can be used as a failover in order to make maintain connection to the internet.

Best regards,

Tomas.

Comments

Thanks Tomas. I’m not really concerned about using them simultaneously.  I really just want to use one as a primary and one as a backup.  It seems I can’t switch between SIMS though because whichever SIM is in slot 1 gets data “connected” and whichever sim is in slot 2 says data “disconnected” even if I make it the primary sim slot 2 it never connects data. If I revert back to sim 1 it will connect data as normal.  Hope that makes sense. Thanks!

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In that case the SIM card won't switch over automatically unless it's configured to do so specifically due to some reason. To configure SIM switch, please login to WebUI and navigate to Mobile>SIM Switch, enable the service and configure the settings as desired. 

More information can be found on our wiki article here: https://wiki.teltonika-networks.com/view/RUT955_Mobile#SIM_Switch.

Let me know if this solves your issue.

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Unfortunately the SIM switch does not resolve the issue of my T-Mobile card showing up with a Disconnected status for data connection.  The general behavior seems to be this:

1. SIM 1 is active

2. Shut down SIM 1 or force switch to SIM 2

3. SIM 2 comes up and establishes a connection with the carrier.  The interface even gets an IP address.

4. SIM 2 never establishes a data connection and remains in the "disconnected" state for data connection state.

5. Switch back to SIM 1 and it comes up and data connection is established.  

That said, it doesn't seem to matter which SIM card (ATT or T-Mobile) is in SIM 1.  It will always be SIM 1 that is able to get a data connection and SIM 2 cannot.  

Thanks again for your support.

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Every other product with 2 SIM card slots will connect to the operator using the default SIM card and, in case the primary connection goes down, the secondary SIM card can be used as a failover in order to make maintain connection to the internet.

That doesn't seem to make sense, in the context of setting both SIM slots in Load Balance mode, where each SIM will simultaneously handle x% of the load, as defined by the policy. I set mine to be 50/50, but that second SIM card never comes up, and never shows as "Online". It used to when I first got the device, but now no longer does (RUTX11 in my case).

Did I buy the wrong device, based on the marketing materials and reviews I've read? It was stated that it would allow both SIM cards to work in either Failover or Load Balance mode, but that doesn't appear to be the case.

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@botches

Did you set the "Check interval" on both SIM cards as well as selected an action on both SIM cards? It needs to be set on the secondary SIM as well to make sure the router knows what to do in case the primary connection is back online.

If that doesn't help, could you please generate and send me over a troubleshoot file via private message?

What's a troubleshoot file and how to generate it?

A Troubleshoot file contains a device's event logs, configuration files and other info useful for diagnostics. It can be downloaded from your device's WebUI, Troubleshoot page:

System → Administration → Troubleshoot

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@setuid

The load balancing can still be achieved by having one active WAN (wired) interface, one active WWAN interface (WiFi WAN) and/or one active mobile interface. The only device that is able to accomplish load balancing with both SIM cards simultaneously is the RUTX12. If you have more questions regarding this topic, though, please create a new thread as this is a slightly different issue.

Best regards,

Tomas.

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@Tomas.  Thanks for the recommendations.  I made several attempts to go through these settings but had the same outcome.  As it turns out the behavior is extremely inconsistent.  The last time I tried, I was only able to get my T-Mobile SIM to register in the modem but it would work in SIM 1 or SIM 2.  The ATT SIM wouldn't register at all.  The ATT SIM still works in my other modems though.  At one time I also had this same problem in the reverse direction (ATT would register but T-Mobile wouldn't).  This was all without even attempting a failover configuration.  It was too inconsistent.  All of my previous LTE modems (I've had 3-4 of them) have worked fine.  My goal with this modem was to save the hassle of having to swap out a SIM every time I wanted to switch carriers.  I'm sure there is an explanation as to why this is behaving so strangely but I had limited time to return the modem and unfortunately had to decide to send it back.  Thanks again for your support.

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In that case, please generate a troubleshoot file and send it over to me via private message. Ideally, before generating the troubleshoot file, please try to connect/allow your device to try and connect to the operator multiple times. I'm copying the part regarding where to find the troubleshoot file download section on the router from one of my comments up above:

 

A Troubleshoot file contains a device's event logs, configuration files and other info useful for diagnostics. It can be downloaded from your device's WebUI, Troubleshoot page:

System → Administration → Troubleshoot