Services on local server
By Keld Simonsen v0.6 1999-04-17
Setup
The local server is hosted on the address 172.16.1.1 It runs DHCP and to
connect to it you need to do:
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MS windows 95/98:
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my computer -> control panel -> network -> choose TCP/IP on your network
card -> chose properties
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under "ip-address, set it to "obtain an IP address automatically"
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Go to the DNS selection, and you can disable DNS as the server provides
it automatically, (or you can add it to your set of DNS servers as 172.16.1.1).
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Linux/Unix
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execute the program (as root) dhcpcd
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DNS: add 172.16.1.1 in /etc/resolv.conf (maybe not needed)
Services provided
These services are currently provided:
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DHCP - to get you automatically on the network
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web - on http://172.16.1.1/ - access to things relevant to the meeting
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web proxy on 172.16.1.1:80 - may speed up retriving docs considerably (maybe
it does not work)
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anon ftp - on 172.16.1.1 - also accessible at http://172.16.1.1/work/
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lan manager things
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work area - also accessible at http://172.16.1.1/work/
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(printer - HP Laserjet - also prints postscript - not working now)
Things you cannot do (currently)
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Sendmail forwarding
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news reading
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a number of other protocols are not forwarded thru the firewall
Troubleshooting
Try first if you can ping 172.16.1.1
Then try if you can ping outside - ping 193.88.44.42
then try the nameserver - ping www.dkuug.dk
The outside telephone link may be lost from time to time, and thus your
download mail or telnet session. Then please try again.
Security
The local area network is not accessable from the global Internet, but
your machine is visible to others on the LAN. Please note that being on
a network can compromise your security. For example be careful that you
do not expose your disks publically to others. The IP numbers 172.16.*.*
are reserved for use by networks that are not connected to the global Internet,
and in this way nobody from outside can get to the LAN.
Also people on the local area network may listen on the LAN to get privileged
information from you, for example passwords for your mail or other access
information like telnet logins.
Solutions may be to use secure transmission methods such as ssh
and shttp for privileged information.
Server requirements
The server may be running on a intel pentium box running linux redhat 5.2 with
some extra configuration. The major technologies used are DHCP and IP masquerading
and IP forwarding for the network to run just over one external telephone
line. The telephone line may be provided via a 28.800 bps modem, and this configuration
seems to provide adequate facilities for a LAN of say 40 machines - doing
external email and some document retrieval and web browsing.
A description of the setup is available.