DHCP Lease

[shukin]

My Shaw Modem is in Bridge mode as I have my own firewall and wireless equipment behind it.  I have issues with the DHCP assigned IP Address.  For example, if I acquire a lease on one computer, I am not able to release it back and use another piece of equipment.  Let's say PC1 and PC2.  PC1 get the lease (and has had it for a LONG time).  If I do a dhcp /release, the PC will release the address but PC2, once in place will not acquire an address.  If fact, if I try this, I have to call into tech support and have them clean up the leases, etc on their end.

This seems strange to me as there may be a time that I may want to replace PC1 with PC2 and having to call in every time seems a bit unusual.

Does Shaw not support this activity?  Any suggestions welcome

[shaw-tony]

Hey shukin,

Thank you for reaching out! Since your modem is bridged, the modem will pass all routing and DHCP settings to your router. What you can try is to un-bridge your modem, connect directly to the modem (removing the router) to see if you are able to complete the above steps. Otherwise, I'd recommend reaching out to your 3rd party router support here. Let me know if you have any other questions.

Cheers,

Tony | Community Mod.

[shukin]

Thanks Shaw-Tony but the issue is more basic than that.  If I have Two MacBooks, let's call the Mac1 and Mac2.  Mac1 in connected directly to the modem with an ethernet cable.  No other devices in the mix.  If I do a DHCP Release before disconnecting Mac1 and then connect Mac2 to the exact same cable, what is going to happen?  Should Mac2 not get an IP address?

I can repeat this over and over again but Mac2 will NOT get an IP address.  If I replace Mac1, it will almost immediately get the original IP address that it had before releasing and removing it from the connection.

I can call into support and get them to 'reset' everything and Mac2 will finally get an IP address.  Now Mac1 will not get an IP address until I call back in.

Any suggestions appreciated.

[shaw-tony · Accepted solution]

shukin Based on your above scenario. If you unplug the ethernet from Mac 1 and plug it into Mac 2, power resetting the modem (unplugging for 30 seconds) will pull an IP for your Mac 2. If you decide to remove the ethernet and plug it back into Mac 1, another power cycle is required. Your modem is bridged so it will give one dynamic IP. 

We do offer a secondary Free IP, if you have this enabled on your account. You can plug in Mac 1 into the modem's ethernet port #1, and Mac 2 into port#2 so they both can pull an IP.

Also to note, when you are releasing and renewing your IP from the PCs, they are only resetting the connect for the ethernet card and not the modem.

[Ratha77]

Just wanted to hop on and say excellent service Tony. It's so rare to see a CSR actually have knowledge and reply with a well reasoned solution. Well done 👍

[mdk]

@shukin -- @shaw-tony has given the solution, namely to power-cycle the modem, but not so much the "why it works".

It is the Shaw modem that is counting the number of IP-addresses going through it -- namely "one" for a standard account, or "two" (as @shaw-tony suggested, you can get a 2nd IP-address for free), or "three" (if you pay an additional monthly fee).

> I have my own firewall and wireless equipment behind it.

A "standard" account is allowed to connect just one device directly to your "bridged" modem. So, switching from PC1 to PC2, when each device is directly-connected to the modem, will require a power-cycle of the modem.

Does your "firewall and wireless equipment" consume an IP-address? So, does your account have 2 IP-addresses provisioned -- one for this equipment, and one for the directly-connected PC1 ?

Is your "firewall and wireless equipment" just a "hub" or a "switch" or a "router" ?  A hub (and a switch) just transmit traffic, but a router issues "private" IP-addresses to many devices connected (wired or wireless) to it -- not IP-addresses assigned by Shaw.

If you connect PC1 / PC2 / MAC1 / MAC2 directly to the cable-modem, you are bypassing your "firewall", and you are relying on the built-in firewall software inside Windows 10 and MacOS. Is that your intent?

[shaw-tony]

@Ratha77 thanks for the kudos. This made my day and I really appreciate that! 😍

[Ratha77]

Hey man, appreciate the reply, honestly you deserve it! You knew exactly how to help, and answered beautifully. You're in the right line of work and it's so refreshing seeing someone with good trouble shooting skills. Hope you stay on and SHAW CABLE GIVE TONY A RAISE. THE PUBLIC NEEDS MORE TONYS!