MSR810-LM采用3G SIM卡VPDN拨号后无法获取正确的ip地址的解决办法

客户需求：在MSR810-LM采用3G SIM卡通过VPDN拨号，接入电信4G运营商获取固定ip地址。

出现问题：在MSR810-LM采用3G SIM卡通过VPDN拨号后获取地址不固定，导致地址获取异常时无法接入网络。

客户案例：

在MSR810-LM采用3G SIM卡通过VPDN拨号后获取地址10.122.13.2后才能正常访问网络，但是发现每次设备重新拨号后获取地址不固定，获取到其它地址时无法访问网络

对比4G接口信息：发现地址获取正确情况下Current Data Bearer Technology（当前载波制式）为：CDMA2000 HRPD；地址获取不正确情况下Current Data Bearer Technology（当前载波制式）为：CDMA2000 EHRPD

原因：运营商服务器侧对拨号获取的地址有限制，只有选择正确的载波制式，获取正确ip地址才能访问网络。

[ls3G]dis cellular

Cellular1/0:

Modem State:

  Hardware Information:

    Model: U8300C

    Manufacturer: LONGSUNG

    Modem Firmware Version: QA30002.1.6_MV11(4534_1.2.3_L0801)

    International Mobile Equipment Identity (IMEI): 869751026361756

    International Mobile Subscriber Identity (IMSI): 460111125944828

    Mobile Equipment Identifier (MEID): A100005B167B66

    Hardware Version: 30000

    Modem Status: Online

    Modem Status: IPv4 Active.

    Modem Status: IPv6 Unkown.

  Profile Information:

    Profile index: 1 

      PDP Type: IPv4v6

      Header Compression: Off

      Data Compression: Off

      Access Point Name (APN): xzpost.vpdn.xz

      Authentication: CHAP

      Username: ls3g1@xzpost.vpdn.xz

  * - Default profile

  Network Information:

    Current Service Status: Service Available

    Registration Status: Registered

    Current Service: Packet-switched

    Current Roaming Status: Home

    Current Data Bearer Technology: CDMA2000 EHRPD

    Network Selection Mode: Automatic

    Current IP address Mode: IPv4 Cellular-alloc

    SID: 0x0

    NID: 0x0

    BID: 0x0

  Radio Information:

    Technology Preference: 1xEV-DO only

    Technology Selected: 1xEV-DO

    Configured LTE Band = 1,3,5,38,39,40,41

  HDR (1xEVDO) related info:

    Current RSSI: -41 dBm

    Current ECIO: -4 dBm

    Current IO: -37 dBm

  Modem Security Information:

    PIN Verification: Disabled

    PIN Status: PIN Requirement Disabled

    Number of PIN Retries Remaining: 3

    Number of PUK Retries Remaining: 10

    SIM Status: OK

        ICCID: 89860317432039303197

  Error Information:

    IPv4 dialing failed: 0x00: No error in the request

    IPv6 dialing failed: N/A

GPS Information:

  GPS Info:

    GPS State: Enabled

    GPS Mode Configured: Standalone

    Latitude: 0 Deg 0 Min 0 Sec North

    Longitude: 0 Deg 0 Min 0 Sec East

    Timestamp (UTC): 06/27/2018  04:12:04

    Local time: 06/27/2018  04:12:04

    Heading: 0.00, Velocity Horiz: 0.00, Velocity Vert: 0.00

    Height (MSL): -18.00 m

  Satellite Info:

解决方法：

关闭EHRPD方法
system
controller cellular 1/0
sendat ate0
sendat at+ehrpdenable=0
modem reboot