In message <009201c985c0$aff05cb0$f9281...@wipro74039c7ca>, "Ashish" writes: > Hello All, > > Thank you for your replies. > > Our configuration file is fairly simple (I have changed the domain name for > security).
You care about security yet you run BIND 4? > domain example.group.net > cache . /etc/dnscache > > We use BIND 4. Actually our DNS was doing lot of CPU utilization and when we > started it in Debug mode we found that there was a reverse lookup for some > IP address which was in the dnscache file. (dnscache is the root hint file) > > This started zone updates, as we can observe in the debug file which calls > function db_update() > > Here is the debug file content (I have modified the IP address for security > reasons. Here 21.x.x.x is one of the entries in dnscache file. I mean that > there was a network address starting with 21 in our dnscache file) > > dgram from 1.2.3.4, 22222 (2222) > ns_req() > req: nlookup(5.6.7.21.in-addr.arpa) id 111 type=11 > req: found '5.6.7.21.in-addr.arpa' as '21.in-addr.arpa' (cname=0) > findns: np 0x6b41e > findns: 2 NS's added for '21' > ns_forw() > qnew(x45gte8) > nslookup(nsp=x2433d,qp=xfdgfv4) > nslookup: NS server01.example.grp.net c1 t2 (x0) > nslookup: 1 ns addrs > nslookup: NS cerver01.example.grp.net c1 t2 (x0) > nslookup: 2 ns addrs > nslookup: 2 ns addrs total > retrytime: nstime 0ms. > schedretry(0x1dfd8, 4sec) > > Dgram from 21.x.x.x > Ns_req() > Qfindid(12345) > USER response nsid=xxxx id xxxx > Respose from upexpected source 21.x.x.x > Stime zzzzz/zzzzz now yyyyyy/yyyyyy rtt x > NS #2 addr 21.x.x.x used rtt y > NS #1 21.x.x.x rtt now z > Resp: ancount 0, aucount 1, arcount 0 > Doupdate(zone 0, savens x, flags y) > Doupdate: dname 21.in-addr.arpa type 6 class 1 ttl 600 > Db_update(21.in-addr.arpa, 0x12345, 0x56789, 087, 0x76543) > > This is strange, there was NSLOOKUP for some IP 5.6.7.21 which caused zone > updates and we do not have any zone specified in our configuration file. zone 0 is the cache. The cache was updated. Mark > Kindly advice > > Thanks > Ashish -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: mark_andr...@isc.org _______________________________________________ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users