Queries are "lost" ??

[Serge Tchesmeli]

Hello to everybody.

First of all, excuse my english, i'm a french user.

My problem:

Our compagny use amanda to make backup of approximalty 400 servers.
When amanda job start, it make two DNS query: a "hostname" and a "reverse".

Since now 2 month, everyday we have some hosts that have not been backuped by 
amanda because the DNS query had failed. Hosts are never the sames, and the 
query failed on direct or reverse query.

I have mirrored the switch port where my dns server is pluggued, and i have 
captured all packets and what i see is:

- amanda query is captured
- DNS server don't answer to this query

I have put "severity debug 9" on all named channel logging and i do not see 
any kind of error in logs.

So my question:
- Can bind "miss" or "refuse" some query because of "overload?" and if yes, 
can we log that?

system info:

- bind 9.2.4 RC2, chrooted
- Linux  2.4.20-13.7custom #3 SMP (BI PIII 500Mhz, 1Go RAM)
- Red Hat Linux release 7.2 (Enigma)

Bind stats:

--- Statistics Dump --- (1102608300)
+++ Statistics Dump +++ (1102608600)
success 16645093
referral 1
nxrrset 583904
nxdomain 3921475
recursion 138245
failure 23020
--- Statistics Dump --- (1102608600)
+++ Statistics Dump +++ (1102608900)
success 16674759
referral 1
nxrrset 585073
nxdomain 3929061
recursion 138492
failure 23034
--- Statistics Dump --- (1102608900)

Ask me if you need more info.
thanks

Serge