Hi Folks,
A couple of distinct questions.
1. Computers on a LAN are "behind" an ADSL modem/router which faces out to the Net.
Seen from outside, this router has IP address
PPP.QQQ.RRR.SSS
From inside the LAN it can be accessed either from the above address or from an "internal" IP address
192.168.1.1
On the LAN are sundry machines with IP addresses
192.168.1.yyy
or (on a subnet)
192.168.0.zzz
Question: Is there any way by which one can address one of the "internal" machines from outside (i.e. the Net).
Clearly, for instance,
telnet PPP.QQQ.RRR.SSS
would at best connect to the router (which does respond to telnet, by the way).
What I'm wondering is if there's anything like
telnet @PPP.QQQ.RRR.SSS!192.168.1.yyy
i.e. to "route" the telnet request for connection to the internal machine at 192.168.1.yyy through the externally visible address PPP.QQQ.RRR.SSS
2. This one's a real Linux question!
Suppose the internal machines, instead of having static IP addresses set up on them, get dynamic IPs handed out by the router.
With the static IPs, each machine can have a /etc/hosts file which associates the IP address with the machines name within the LAN, including a short "nickname". E.g.
192.168.0.6 brandy.my.home.lan brandy br so, e.g., in the LAN I can do "telnet br".
But, with dynamic IPs, this association would break down. "brandy" would no longer have IP address 192.168.0.6
So -- What's the equivalent mechanism when dynamic IPs are used? If I do
telnet br
would this simply not work (because there's no IP/name association), or is there a mechanism whereby allocation of a dynamic IP address to brandy.my.home.lan would set up an association with this name (and to chosen nicknames "brandy", "br") as in the /etc/hosts file?
And, if so, where does it (and its components) reside?
Thanks, and best wishes to all, Ted.
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