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assign a subnet via PPPoE

Posted: Thu May 17, 2012 6:13 pm
by chrpinedo
Hello,

I'm new to PPPoE and Mikrotik so please apologies for a such basic question. I would like to know if it's possible to assign a subnet to a PPPoE-client instead of an unique address "\32".

Framed-IP-Address=192.168.1.1
Framed-IP-Netmask=255.255.255.0

If I assign a /24 network to a PPPoE client. Mikrotik router generates two routes:

- One connected /32 route: 192.168.1.1/32
- One static route: 192.168.1.0 -> 192.168.1.1

This is correct to support a network assignment??
I'm a bit confusing because are overlapping routes.
The PPPoE client needs some special support to be able to receive a network instead of one IP Address??

Thanks in advance,

Christian

Re: assign a subnet via PPPoE

Posted: Thu May 17, 2012 6:41 pm
by dleo
Hi,

I had been reading the RFC 2516, and i don't see a AVP that could reply a network subnet.

Anyway, why do you want reply a network subnet?

Re: assign a subnet via PPPoE

Posted: Thu May 17, 2012 7:01 pm
by nickshore
Normally you would assign a subnet from a different range from the IPs used in the PPP connection.

eg use 192.168.1.5/32 for the pppoe and also assign 10.10.10.0/24

Nick.

Re: assign a subnet via PPPoE

Posted: Thu May 17, 2012 8:25 pm
by docmarius
This is correct to support a network assignment??
I'm a bit confusing because are overlapping routes.
That is a correct network assignment.
First the remote ppp interface needs its own IP address and route, that's the /32 route.
Over that one, you route a subnet having that IP as a gateway (and it can be even another subnet as nickshore stated).
The idea is that the more restrictive an address range is (say bigger netmask...) the higher priority it has in the routing process. So the /32 will take precedence over /24 and there is in fact no functional overlapping.
e.g. you could have 192.168.1.0/24 routed via gw1 and 192.168.1.0/30 via gw2 and 192.168.1.1/32 via gw3.
In this case, host 192.168.1.1 will be reacheable via gw3, all traffic for 192.168.1.0, 2 and 3 will go to gw2 and 192.168.1.4..255 will go over gw1.

Re: assign a subnet via PPPoE

Posted: Thu May 17, 2012 9:10 pm
by rodolfo
I assign an IP using 'framed-ip-address' (i.e. 192.168.1.33), also called ptp address
and a subnet using 'framed-route' (i.e. 10.0.1.0/29)

now your subscriber route the 10.0.1.0/29 subnet at the 192.168.1.33 gateway

Re: assign a subnet via PPPoE

Posted: Fri May 18, 2012 11:51 am
by chrpinedo
Uauuu Thanks for all your help, I didn't know the Framed-Router Attribute and it's what I was looking for.
Thanks!!

Christian