Hi, [your mail violates RFC2822 for the In-Reply-To header which breaks threading display, probably a mailer bug]
On 21.05.2007 00:52, Hal Murray wrote: >> If any magic name has to be used, try pool.ntp.org. Maybe not nice, >> but better than a newly invented name. > > If anybody isn't already familiar with the UWisc/Netgear story, here's the > URL: > http://www.cs.wisc.edu/~plonka/netgear-sntp/ > Flawed Routers Flood University of Wisconsin Internet Time Server > I call it required reading for anybody interested in networking. > > Unless you have permission from the owner, it's a really really bad idea to > wire a name or IP address into any system and them ship zillions of those > boxes. That's why I suggested pool.ntp.org. It exists exactly for that purpose. > Even if you do have permission, you should probably use a name or address of > your own in order to avoid an external dependency on some infrastructure that > you don't have any control over. Valid point. >> There is a standard for time serving via DHCP. > That's not time serving itself. That's distributing the IP Address of a time > server. It should have been clear from the context that I meant exactly that. > ntpd doesn't support getting the server address directly via DHCP. But as you show below, it can be fed with the server address obtained via DHCP. > gentoo has a NTP wiki page that includes using DHCP > http://gentoo-wiki.com/HOWTO_NTP > Basically, they are rewriting ntp.conf on the fly > > None of the systems I've worked with have done that. This means the systems you've worked with have room for improvement. > ntpd has a couple of multicast/broadcast modes. They may be appropriate. > I've never worked with them. I gave a few pointers in the mail you replied to. They even deal with network load of such multicast/broadcast approaches. Maybe I should be more verbose next time. > How are the XOs going to find their backup server? You can provide a list of NTP servers via DHCP. Quoting from RFC 2132: "Network Time Protocol Servers Option This option specifies a list of IP addresses indicating NTP servers available to the client. Servers SHOULD be listed in order of preference." In a multicast/manycast/broadcast configuration, having a second NTP server should suffice. Regards, Carl-Daniel _______________________________________________ Devel mailing list [email protected] http://mailman.laptop.org/mailman/listinfo/devel
