Problem with bind system call over slip link

Jeffrey C Honig jch at risci.tn.cornell.edu
Thu Jan 4 14:17:53 AEST 1990


On Tue, 26 Dec 89 14:59:16 PST wrs at niagara.tymnet.com (Bill Soley) writes:
| I don't use cisco SLIP, but I can say this about Sun SLIP: Sun thinks of
| the SLIP line as a network unto itself, not as an interface to a remote
| network.  This means the SLIP line needs its own (unique) network (or
| subnet) number and the interface at each end needs a host number on that
| network (one for cisco and a different one for Sun).  This is the same
| model 4.3 BSD uses.
| 
| Try changing
| 	sc->sc_if.if_flags = IFF_POINTOPOINT;
| to
| 	sc->sc_if.if_flags = 0;		/* was IFF_POINTOPOINT */
| in if_sl.c and rebuilding your kernel.
| 
| Then specify the remote network (subnet) number as the destination in the
| slattach command.

SLIP links are host routes, they do not have a subnet or network
associated with them.  In 4.3 BSD and it's derivatives pointopoint
interfaces should be refered to by their destination address, and their
subnet masks should be ignored.  The local address is not necessarily
unique, multiple pointopoint interfaces can share the same local interface
address with each other and up to one non-pointopoint (Ethernet)
interface.

Jeff



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