Topic: Updating SME IP

[Mark]

External IP (A)     External IP (B)     Internal IPs
++++++++++++           ++++++           +++++++++++
+Cable Modem+___eth0___+SME +___eth1___ +Local Net+
++++++++++++           ++++++           +++++++++++

My router is assigned a dynamic External IP (A) from my ISP.  The SME is assigned External IP (B) from the cable modem.  My problem is when the ISP changes the cable modem's IP, the SME still thinks the modem has the old IP.  As a result, the local net looses the connection to the net.  How can I get the SME to refresh it's network connection when the ISP changes the cable modem IP?

[Charlie Brady]

Mark wrote:

> My router is assigned a dynamic External IP (A) from my ISP.

You don't show a router in your network diagram.

> The SME is assigned External IP (B) from the cable modem.

Is this allocated via DHCP?

> My
> problem is when the ISP changes the cable modem's IP, the SME
> still thinks the modem has the old IP.

Thinks? It doesn't think.  What tells your SME server what the IP address is? If it's not DHCP, then what is it? If it is DHCP, then it should "just work".

> As a result, the
> local net looses the connection to the net.  How can I get
> the SME to refresh it's network connection when the ISP
> changes the cable modem IP?

How or why is the ISP changing the cable modem IP?

Charlie

[Mark]

Mark wrote:

  > My router is assigned a dynamic External IP (A) from my ISP.

  You don't show a router in your network diagram.

I mean the cable modem (thought that is a router).

  > The SME is assigned External IP (B) from the cable modem.

  Is this allocated via DHCP?

Yes

  > My
  > problem is when the ISP changes the cable modem's IP, the SME
  > still thinks the modem has the old IP.

  Thinks? It doesn't think. What tells your SME server what the IP address is? If it's not DHCP, then what is it? If it is
  DHCP, then it should "just work".


DHCP from the cable modem. Sorry for the amaturish wording. But I am one.

  > As a result, the
  > local net looses the connection to the net. How can I get
  > the SME to refresh it's network connection when the ISP
  > changes the cable modem IP?

  How or why is the ISP changing the cable modem IP?


I suppose the lease expires from the ISP to the cable modem. Probably to make people pay for a static IP.  But for some reason the SME doesn't pick up a new external IP.  Only if I reboot the SME gets a new external IP.


Mark

[Charlie Brady]

Mark wrote:

>>   Thinks? It doesn't think. What tells your SME server what
>> the IP address is? If it's not DHCP, then what is it? If it is
>>  DHCP, then it should "just work".
>
> DHCP from the cable modem. Sorry for the amaturish wording.
> But I am one.

??

You still haven't answered my questions. What leads you to think that the ISP has allocated a different IP address, and what leads you to think that the SME server is still using a previous one?

Are there references to dhcp in /var/log/messages?

As I said, DHCP should "just work". If it doesn't, it could be a hardware (or driver) problem (therefore not related to DHCP at all), or it could be a bug in either the client or server end of the DHCP transaction.

People here may be able to help you if you just describe the symptions you see, rather than try to interpret them.

Charlie

[Mark]

>>> Thinks? It doesn't think. What tells your SME server what
>>> the IP address is? If it's not DHCP, then what is it? If it is
>>> DHCP, then it should "just work".
>>
>> DHCP from the cable modem. Sorry for the amaturish wording.
>> But I am one.


>You still haven't answered my questions. What leads you to think
>that the ISP has allocated a different IP address, and
>what leads you to think that the SME server is still >using previous one?


My setup:
ISP----CableModem----eth0---SME---eth1---LocalNet

The fact that the cable modem is connected to the ISP leads me to believe the ISP controls the dhcp leases.  When I reboot the SME, the external IP for the cable modem has changed as shown in the output of "arp -a".  Also, the external IP of the SME has changed as shown in the output of "ifconfig"

>Are there references to dhcp in /var/log/messages?

There are successful DHCP lease renewals from previous attempts.  I not at the SME at the moment so can't provide more details.

>As I said, DHCP should "just work". If it doesn't, it could be a >hardware (or driver) problem (therefore not related to DHCP at >all), or it could be a bug in either the client or server end >ofthe DHCP transaction.

>People here may be able to help you if you just describe >the symptions you see, rather than try to interpret them.

I'm trying.  Thanks for the attempt.

[Rob Wellesley]

Suggest you post your ISP's name  - perhaps there is someone with the same ISP who can help.

Also - have you tried your ISP's helpdesk?

rob

[Mark]

Have not talked to the ISP.  I like to let sleeping dogs lie .  But just to clarify, every time the local net looses connectivity to the internet,  I can't ping the cable modem. I reboot the SME and both the cable modem and SME have new external IPs.  If the local net does Not loose connectivity and I reboot the SME, the IPs for both the cable modem and SME are unchanged.

[Gregory Baird]

Hello

Are you using a router you mention it if you are
your sme box just needs the gateway ip of the router
something like 192.168.1.1 if wll find it's way from there

if you are using your sme box as the gateway it
should be set to dchp on your first nic - eth0 your network will use the ip # of eth1 as it's gateway

your eth0 is setup by using the gateway setup in your sme box - set to dchp and that will allow it to update itself

your router if you use one works the same way

Greg