Subnet Mask, help, or something

Soldato
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Hey guys, just a quick question, or maybe a long one, depending on how you see it

Subnet Masks, do they have an impact on the router working???

My RP614 router has been working 100% for god knows how long, and now it doesnt.....one thing that has changed is the Subnet Mask on the Modem, (i know this when i directly connect the modem to PC) it was the normal 255.255.255.0 but now the last .255 is now .254 and the router will not work, modem and router do not communicate, ive done the usual reboot of them all and messed around with the normal settings...


I need help please.
 
Soldato
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Subnet mask is very important as it tells the router/modem where to send traffic. The subnet mask has to fit in with the subnet address because otherwise the number of "borrowed" bits will not fit and the network part of the address will go bonkers.
I guess, in a nutshell, the subnet mask tells the computer, which part of the address is a network portion, and which part is a host.

Post your IP and subnet mask and required amount of subnets and i'll sort it out for you. :)
 

Imy

Imy

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The following is a rough guess as to whats happening:

Since the subnet mask is set on your modem, this means its set by your ISP. By going from a subnet mask of 255.255.255.0 to 255.255.254.0 all they've done is restructure their subnets to have 510 usable hosts instead of 254. I'm not sure how this could cause a problem.
 
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Soldato
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basically, ive rebooted the router and modem, at different intervals, modem first, router second, and then vica versa, ive tried setting manual IP's to no effect, ive Rang my ISP but they dont deal with routers (blueyonder), im at a real loss here, and from what i can see, its not something ive done, as the day it happened i wasnt even in.
 

Imy

Imy

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On your router's home page it says "connects up to 253 network users". That indicates a subnet mask of 255.255.255.0. Not sure if that's important. I'll have quick look at your router's manual. In the meantime you might want to try a firmware upgrade on your router.
 
Soldato
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thats the thing, when everything is connected correctly, i cant get to the router config page or modem page, the 2 seem to hate each other right at this moment, so im all confused, and im about ready to throw everything out the house and forget about all this internet stuff.
 
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