On Sat, 2006-08-05 at 14:00, Erik P. Olsen wrote: > >> I have several PCs/LapTops accessing the Internet through a wireless router > >> (Linksys WRT54G). It also acts as a DHCP server presenting each connected PC > >> with an IP-address. For Internet access it works flawlessly but I have other > >> application which access the PCs on the LAN, such as back-up programs (Bacula). > >> > >> For the last sort of applications I need to have either a static IP-address or > >> an allways correct association between workstation name and its IP-address > >> (/etc/hosts). It so happens that if the configuration (in terms of connected > >> PCs/LapTops) remains static then the boxes get the same IP-address each time > >> they connect to the router. This is, however, not allways true if the > >> configuration is dynamic (many different PCs and not allways the same). > >> > >> I feel that what I really need is a DSN on the LAN which is being updated each > >> time a box connects to the router and gets an IP-address. I have noticed that > >> some people disable the DHCP server in their router and establesh a DHCP server > >> in one of connected PCs, but I don't see how that can be accomplished and what > >> happens if that server is taken out of the network? > >> > >> Is there a way out of this problem? > > > > I'm not sure I understand you correctly, but what about giving this > > (backup) host a static ip address outside the dhcp range but obviously > > in the same network ? Just narrow down the dhcp range on the router if > > necessary. > > OK. Let me explain it more specific. In the back-up config files I can address > the clients (the PCs to be backed up) by either their IP-addresses or their > hostnames (I think Windoze calls it workstation names). IP-addresses are dynamic > and may change, host names are static Errr... I wouldn't call a name that any user can change on a whim "static". > so I can enter their host names into the > config files to keep them static provided I have a dynamic way of modifying > /etc/hosts whenever a box connects to the LAN. /etc/hosts is in a sense a DNS I > just don't know of any method to keep it current. The best approach to this is to go into the DHCP server and tie the IP addresses it gives out to the specific ethernet MAC addresses of the target PC's so they will always be the same when they are connected to this network. Most DHCP server provide some way to do this. If the PCs never move you can also do static assignments on the client side. Then if you have enough machines that maintaining host file entries is a problem, set up your own DNS server with a real or fake domain for your LAN. Also, if the only issue is backups, you might want to look at backuppc: http://backuppc.sourceforge.net/. Among other nice features, it can find windows DHCP targets by their netbios names. -- Les Mikesell lesmikesell@xxxxxxxxx
