My idea for a heuristic was indeed extremely simple. In case the first name server has a non public ip address, auto switch to strict order.
Il giorno 27/mag/2012, alle ore 23:04, Simon Kelley <si...@thekelleys.org.uk> ha scritto: > Thomas in #17 > > A heuristic for this is difficult, because you have to prove a negative. > If we can assume the first nameserver has local addresses, we can never > return a reply from any other nameserver until we have the reply from > the first one, in case the first one has different data. Once we see > different data from different nameservers, we can go to --strict-order > mode, but the opposite is not true: the same answer for a particular > query doesn't guarantee that the answers to future queries will always > agree. There's no way to be sure that the nameservers are equivalent > based on the history of returned queries. Unless we can assume that, we > always need to wait for the first nameserver to reply (or a timeout) and > have to stay in --strict-order mode forever. > > There is one possibility, which is to assume that nameservers are > equivalent, but switch to --strict-order mode if conflicting replies are > seen. When a query is forwarded to all available servers, and the first > reply sent back to the original requestor, keep the record of the reply > (at least, a bit indicating NODATA/NXDOMAIN or a valid reply. If another > reply comes in later from another nameserver which conflicts, then > switch to --strict-order mode. This will not get the first queries > right, but it will be triggered eventually (and it might be triggered, > swicthing mode forever, by random server glitches) > > For a single-host cache, --strict-order might be the simplest fix...... > > Simon. > > -- > You received this bug notification because you are subscribed to a > duplicate bug report (993794). > https://bugs.launchpad.net/bugs/1003842 > > Title: > Precise NM with "dns=dnsmasq" breaks systems with non-equivalent > upstream nameservers > > To manage notifications about this bug go to: > https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1003842/+subscriptions -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1003842 Title: Precise NM with "dns=dnsmasq" breaks systems with non-equivalent upstream nameservers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1003842/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
