On 2009-05-25 13:21, carlopmart wrote: > Paul Bijnens wrote: >> On 2009-05-25 12:51, carlopmart wrote: >>> I have a problem using named with different CentOS5 servers (2 servers): all >>> they are really slow to resolv any internet address and most of time fails to >>> resolv. This situation differs if I use "forwarders" servers like opendns: >>> resolving names it is really really quickly. And I don't understand why. >>> >>> On the other hand I have tested three DNS servers using Windows 2003, Windows >>> 2008 and Ubuntu hardy and these problems doesn't occurs (I don't need to >>> configure forwarders on any of them): all resolves any name and really fast. >>> >>> IPv6 is disabled on both CentOS servers. Somebody knows why these dns servers >>> are slow?? >> >> My crystal ball is in repair. Could you in the meantime add some more >> hints, e.g. your config files, and how you diagnosed the slowness. >> >> My CentOS5 DNS-servers do resolve really quickly, with or without forwarders. >> >> > Ok, my named.conf: > > // > // named.conf > // > > options { > directory "/var/named"; > dump-file "/var/named/data/cache_dump.db"; > statistics-file "/var/named/data/named_stats.txt"; > memstatistics-file "/var/named/data/named_mem_stats.txt"; > listen-on port 53 { 127.0.0.1; 172.25.50.10; }; > version "DNS Server v2.0"; > dnssec-enable no; > query-source port 53; > forwarders { 208.67.220.220; 208.67.222.222; }; > }; > > logging { > channel security_channel { > file "/var/named/data/security.log" versions 3 size 1m; > severity debug; > print-time yes; > print-category yes; > print-severity yes; > }; > channel default { > syslog local4; > severity info; > print-category yes; > print-severity yes; > }; > channel query_log { > file "/var/named/data/query.log" versions 3 size 1m; > print-time yes; > }; > category security { > security_channel; > default; > }; > category queries { > query_log; > }; > channel default_debug { > file "/var/named/data/named.run"; > severity dynamic; > }; > category lame-servers { null; }; > category default { default; }; > }; > > controls { > inet 127.0.0.1 allow { localhost; } keys { rndckey; }; > }; When you're not using forwarding, the dns server should have some basic knowledge of the root servers. So add something like: // prime the server with knowledge of the root servers zone "." { type hint; file "/path/to/the/file/having/named.root"; }; And the file itself can be downloaded (and updated now and then) from: http://www.internic.net/zones/named.root And to avoid forwarding on silly resolutions for localhost or 127.x.x.x you can do the same with a local "type master" zone for those two zones as well: // be authoritative for the localhost forward and reverse zones zone "localhost" { type master; file "/path/to/the/file/having/localhost.zone"; }; zone "127.in-addr.arpa" { type master; file "/path/to/the/file/having/ptr-127.zone"; }; -- Paul Bijnens, Xplanation Technology Services Tel +32 16 397.525 Interleuvenlaan 86, B-3001 Leuven, BELGIUM Fax +32 16 397.552 *********************************************************************** * I think I've got the hang of it now: exit, ^D, ^C, ^\, ^Z, ^Q, ^^, * * quit, ZZ, :q, :q!, M-Z, ^X^C, logoff, logout, close, bye, /bye, ~., * * stop, end, ^]c, +++ ATH, disconnect, halt, abort, hangup, KJOB, * * ^X^X, :D::D, kill -9 1, kill -1 $$, shutdown, init 0, Alt-F4, * * Alt-f-e, Ctrl-Alt-Del, Alt-SysRq-reisub, Stop-A, AltGr-NumLock, ... * * ... "Are you sure?" ... YES ... Phew ... I'm out * *********************************************************************** _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos