I am having an issue with some Sierra Wireless MC755 modems.
These have Verizon SIM cards in them and previously had static public IP’s from Verizon. We recently transitioned to a VPN so I need to assign private IP’s to these modems as our VPN address pool is static. The problems that I am having are:
- The network settings in Network and sharing center are blank. Even if I set them to manual, enter my information, leave and come back, they will be blank. The DNS server settings stay though.
- the IP address and name servers will stick but something is changing the subnet mask and gateway.
So, say I set the following IP settings on the settings on the ‘Cellular 2’ connection, ipv4, ‘Use the following IP Address’:
IP: 10.10.10.2, Subnet: 255.255.255.0, Gateway 10.10.10.1
If I then run ipconfig I will see that IP address and name servers stay but the net mask will always, no matter what I do, change to 255.255.255.252 and the gateway will always, no matter what I do change to one IP above whatever was set as the IP address. So, for example, if I set the IP to 10.10.10.2 the gateway will be 10.10.10.3.
it doesn’t matter what IP I use in any range this will always happen.
Here are some examples to hopefully clear up what I am talking about:
I manually set IP: 10.10.10.5, Netmask: 255.255.255.0, Gateway: 10.10.10.1
Ipconfig will show: IP: 10.10.10.5, Netmask: 255.255.255.252, Gateway: 10.10.10.6
I manually set IP: 10.10.10.25, Netmask: 255.255.255.0, Gateway: 10.10.10.1
Ipconfig will show: IP: 10.10.10.25, Netmask: 255.255.255.252, Gateway: 10.10.10.26
Etc, etc, no matter what I do. As stated in (1) above, every time I go into the adapter settings to change the IP settings the IP address, Subnet mask and Default gateway fields are blank even though ‘Use the following IP address’ is still selected.
Verizon is claiming that this is something the MC7355 firmware is doing. Hopefully someone on here will have an idea of why this is happening an maybe something I can do to fix it? Are there some AT commands I can use to set these on the modem itself or to tell the modem to stop changing these settings and use the settings I enter into the IP configuration of the adapter?