From mboxrd@z Thu Jan 1 00:00:00 1970 From: peter at rulingia.com (Peter Jeremy) Date: Sun, 2 Sep 2018 08:20:55 +1000 Subject: [COFF] =?utf-8?q?=5BTUHS=5D_RetroNet=E2=80=A6_Virtual_is_cheap=2E?= In-Reply-To: <0b739af0-da9e-6bdb-fe17-6f2dda837de5@spamtrap.tnetconsulting.net> References: <1535565898.3905695.1490376112.4B7D3E18@webmail.messagingengine.com> <6e7783fb-ff06-2e21-002f-76bef263b63c@spamtrap.tnetconsulting.net> <1d8c0539-8b43-9954-d8a7-db4dcc22b27d@texoma.net> <0b739af0-da9e-6bdb-fe17-6f2dda837de5@spamtrap.tnetconsulting.net> Message-ID: <20180901222055.GA71355@server.rulingia.com> On 2018-Aug-31 11:33:19 -0600, Grant Taylor via COFF wrote: >On 08/31/2018 10:24 AM, Cornelius Keck wrote: >> But, I liked the way to have physical control over my setup, still do, >> so there was, is no reason to switch at this time. Given different >> circumstances, I might. > >I've actually seen / discussed some options to combine the static IP >that you get with inexpensive VPSs with the only dynamic nature of some >residential connections. My approach is a script on the client system (that has dynamic address) that compares its external address with its address in DNS. If they differ, it sends an update to the DNS server. The script is hooked into dhclient so it's invoked when the address is updated or renewed. The "DNS server" is a hack I've added to Iodine[1] - for an "A" lookup, it does a readlink(2) of the FQDN in a config directory and treats the target as an IPv4 address[2]. This FQDN is within a subdomain I've delegated to Iodine - I have a CNAME pointing into the subdomain. The client updates the symlink by SSHing to the DNS server host and running a command that takes the domain name and address and updates the symlink. Whilst I've managed to get a static address at home, I still find it useful for VPSs where the address is static whilst the instance is running but not preserved across rebuilds. As an example, lookup gce1.rulingia.com. [1] http://code.kryo.se/iodine/ [2] This is good enough because Australian ISPs don't believe in IPv6 -- Peter Jeremy -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 963 bytes Desc: not available URL: