On 11/4/19 12:35 PM, Achim Gratz via devel wrote: > Richard Laager via devel writes: >> The default for maxclock is 10. This includes the "pool" entries, of >> which the stock Debian configuration has four: >> pool 0.debian.pool.ntp.org iburst >> pool 1.debian.pool.ntp.org iburst >> pool 2.debian.pool.ntp.org iburst >> pool 3.debian.pool.ntp.org iburst >> >> As a result, the default is to use 6 pool servers. > > That is a cargo-culted configuration from an earlier (buggy) pool > implementation in NTP classic that didn't mobilize enough pool servers > when only a single pool line was present. With recent NTPd you really > only need one pool ine Each of these names (N.debian.pool.ntp.org) resolves to only 4 IPs.* The four of them resolve to (mostly) non-overlapping IPs. In other words, if I resolve only one name, I get 4 IPs, but if I resolve all four names, I get 15 IPs. If I wait 150 seconds for the TTL to expire, I do get more IPs. But using all four names definitely gets me IPs a lot faster, which makes a difference for initial convergence.
* I'm ignoring IPv4 vs IPv6 here and considering only one address family, which is relevant to IPv4-only hosts. Though apparently only one of the four names is returning AAAA records. -- Richard _______________________________________________ devel mailing list devel@ntpsec.org http://lists.ntpsec.org/mailman/listinfo/devel
