Date: Fri, 22 Oct 1999 17:59:35 +0100 From: Robin Melville <robmel@nadt.org.uk> To: "Forrest W. Christian" <forrestc@iMach.com>, Will Mitayai Keeso Rowe <mit@aecinfo.com> Cc: FreeBSD-Stable <freebsd-stable@FreeBSD.ORG> Subject: Re: IP aliasing Message-ID: <v04210104b43647dde2ee@[172.16.17.20]>
next in thread | raw e-mail | index | archive | help
At 12:08 pm -0600 20/10/99, Forrest W. Christian wrote: >On Wed, 20 Oct 1999, Will Mitayai Keeso Rowe wrote: > > > I noticed on another server's box that they alias IP addresses to their > > loopback interface rather than their Ethernet interface. Is their any > > benefit/detriment to doing this? > >Here's the rule I use: > >If the IP address you are adding is "Naturally" on the ethernet add it as >an alias to the Ethernet interface. > >If the IP address is on a different subnet than the Ethernet, add it as an >alias on the loopback. [...snip...] I an interested in this also since we recently were forced by a shortage of addresses to add a logical subnet onto a physical WAN. The situation is that we have a gateway host with interfaces onto a physical subnet and to the WAN. Since the gateway is dual ported it seemed wrong to alias to lo0 as generally advised in the mailing lists since it wouldn't know which NIC to send to. It also seemed wrong to give the alias an 0xffffffff subnet mask since it was talking to an actual, albeit logical, subnet which it needs to send broadcast IP to. Consequently I gave the alias the same settings as if it were another NIC: IP: 172.16.97.1 mask 0xffffff00. The "native" address of the interface is 194.155.224.187/24. Incidentally, this WAN is not visible from the Internet. Nothing horrible has happened, and everything is working fine, but I still worry that I've done something stupid, being so clearly in contravention of the good advice on this list and others. Robin. ---------------------------------------------------------------------- Robin Melville, Addiction Information Service Nottingham Alcohol & Drug Team Tel: +44 (0)115 952 9478 Fax: +44 (0)115 952 9421 work: robmel@nadt.org.uk Pages: http://www.innotts.co.uk/nadt ---------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?v04210104b43647dde2ee>