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AMX EXB-COM2 changing IP all the time

adysadys Posts: 395
in AMX Hardware
Hi all

We have AMX EXB-COM2 connected to NETLINX 3100.
We are connecting with it by its IP address.

From time to time, when the router is down or some connection lost from some reason, the AMX EXB-COM2 is changing its IP so it stop working and I need to config it again.

What is the best way to prevent this from happening?

Thanks,

Ady.

Comments

  • John NagyJohn Nagy Posts: 1,742
    Sounds like you are using DHCP instead of a static address. If so, from page 9 of the manual:
    (the formatting and tables are messed up in the paste... if this looks like your issue, go get the "Operation Reference Guide"...

    Overview
    EXB modules support two IP addressing modes: Static IP , and DHCP (with link-local fallback)
    .
    By default, EXB Modules are set to DHCP Mode. The modules can be configured for either of these modes via two methods:
    The front-panel ID Pushbutton (see the Toggling Between Static and DHCP IP Addressing on page 14).
    Telnet command (see the Terminal (Telnet) Commands
    on page 53).
    Default Parameters For Static IP Mode
    DHCP Mode
    When in DHCP mode (the default setting), the module will a ttempt to get a DHCP lease (consisting of IP address, gateway, and other network parameters). Should it fail to obtain a lease from a DHCP server, it will
    then configure itself for a link-local address.

    EXB modules utilize a modified link-local addressing procedure: the
    first address to be tried is a known address in the link-local space:
    169.254.2.2. That address will be probed, and if unclaimed
    will be used by the EXB module.

    If 169.254.2.2 is already claimed, the EXB module will choose a random address within the 169.252.x.x link-local address space (again probing to ensure that it is unclaimed).
    Once operating with a link-local address, the device will periodically re-try DHCP,
    and re-assign the IP to a valid DHCP grant if successful.
    At any time, if the device determines that its IP address has changed, it will disconnect from the Master (if necessary, depending on the connection state), and then reconnect to the Master.

    TCP/IP Address Configuration
    EXB modules support IPV4 network addresses, gateway addresses, DNS server addresses, and network name. EXB modules support Nexus Discovery Protocol (NDP) capabilities as well
    as IP discovery via NetLinx Studio.
    "Link-Local Fallback" is a method by which an IP host can derive a local network-
    unique IP address, by negotiating with the other IP hosts on the same network, as a
    fallback from DHCP. Link-Local can also be used in its own right as the primary
    method of IP address allocation. See "DHCP Mode" below for details.
    Default Parameters For Static IP Mode
    Address:
    192.168.1.2
    Netmask:
    255.255.255.0
    Gateway:
    192.168.1.1
    DNS1:
    192.168.1.1
    DNS2:
    192.168.1.1
    DNS3:
    192.168.1.1
    NDP stands for "NetLinx Discovery Protocol", a device discovery method used by
    NetLinx Masters. With NDP Beacon enabled, the Master will transmit NDP beacons
    for AMX's proprietary device discovery
  • adysadys Posts: 395
    Thank you very much for the info!

    I don't understand why the device address is changing.

    I declared it in code as 32001:2:1 and from the online tree I can see it has been changed to 32001:2:1.

    Is the IP change cause that?

    Thanks again,

    Ady
  • rfletcherrfletcher Posts: 217
    32001 is in the dynamic device range. Devices in that range do not have set IDs, they get whatever the next ID in the range that is available when they connect. If they fall offline they can wind up with a different ID if something else connects dynamically. I usually start numbering my EXBs and DXLINK boxes from 5002 upwards.
  • adysadys Posts: 395
    So that is my problem, and not the IP...

    How can I set an id ?
    Its getting it automatically, no?

    That what I see in the system device tree, its 32001 for few months, and then changing to 32002 from some reason, so I had to change it in the code.
  • rfletcherrfletcher Posts: 217
    adys wrote: »
    So that is my problem, and not the IP...

    How can I set an id ?
    Its getting it automatically, no?

    That what I see in the system device tree, its 32001 for few months, and then changing to 32002 from some reason, so I had to change it in the code.

    Either use Diagnostics->Device Addressing in Studio or telnet to the EXB and send "set device <device id>" (iirc)
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