13 Apr
2017
13 Apr
'17
10:08 a.m.
On 04/13/2017 12:12 AM, Nk via lime-users wrote:
I’m wondering though, since every node, at least in
our network, has the
10.13.0.1 IP on the lan side, how are conflicts avoided or solved when a
device with IP 10.13.0.108 - for example - roams to a WLAN of a node
where a device with such IP is already present? Or are IP leases
monitored network-wide to avoid two devices having the same IP at the
same time anywhere on the network?
I hope I got your point...
There's a package in lime-packages named "dnsmasq-lease-share" [1] and
included in normal LiMe images, this shares a file with the leases using
Alfred (a Batman adv utility). Have a look at these files [2].
So the leases list is shared among the whole Batman adv cloud.
If you move from a Batman cloud to another (which is less usual) the
collisions are avoided (well, reduced enough) by the %N1 parameter in
10.%N1.0.0/16 [3].
Moreover there should be some kind of check of IP availability any time
an IP is assigned, don't know really.
And if so, how big a pool do you need
to always accomodate such vast numbers of clients?
Mmh?
As there's this lease share mechanism, you don't need a pool much bigger
than the number of your clients.
In absence of such mechanism, you could calculate the probability of a
collision as in "birthday paradox" [4].
Bye!
Ilario
[1]
https://github.com/libremesh/lime-packages/tree/develop/packages/dnsmasq-le…
[2]
https://github.com/libremesh/lime-packages/blob/develop/packages/dnsmasq-le…
[3]
https://github.com/libremesh/lime-packages/blob/develop/packages/lime-syste…
[4] https://en.wikipedia.org/wiki/Birthday_problem