Today the master dns server of an internal network subdomain failed and the slave server cannot find names in the replicated zone
Querying the server
nslookup ns1.sis.trt 10.3.190.61
Server: 10.3.190.61
Address: 10.3.190.61#53
** server can't find ns1.sis.trt: NXDOMAIN
nslookup gitlab.sis.trt 10.3.190.61
Server: 10.3.190.61
Address: 10.3.190.61#53
** server can't find gitlab.sis.trt: NXDOMAIN
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6_10.1 <<>> @10.3.190.61 gitlab.sis.trt
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 1832
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;gitlab.sis.trt. IN A
;; Query time: 0 msec
;; SERVER: 10.3.190.61#53(10.3.190.61)
;; WHEN: Thu Dec 19 09:33:22 2019
;; MSG SIZE rcvd: 32
My bind9 slave configurations
/etc/named.conf
options {
listen-on port 53 { any; };
listen-on-v6 port 53 { ::1; };
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";
allow-query { any; };
allow-transfer { none; };
recursion yes;
dnssec-validation no;
/* Path to ISC DLV key */
bindkeys-file "/etc/named.iscdlv.key";
managed-keys-directory "/var/named/dynamic";
};
logging {
channel default_debug {
file "data/named.run";
severity dynamic;
};
};
zone "." IN {
type hint;
file "named.ca";
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";
zone "sis.trt" {
type slave;
file "/etc/named/zones/db.sis.trt";
masters { 10.3.190.60; };
};
zone "3.10.in-add.arpa" {
type slave;
file "/etc/named/zones/db.10.3";
masters { 10.3.190.60; };
};
/etc/named/zones/db.sis.trt
ORIGIN .
$TTL 3600 ; 1 hour
sis.trt IN SOA ns1.sis.trt. soa.sis.trt. (
2019121101 ; serial
600 ; refresh (10 minutes)
300 ; retry (5 minutes)
3600 ; expire (1 hour)
3600 ; minimum (1 hour)
)
NS ns1.sis.trt.
NS ns2.sis.trt.
$ORIGIN sis.trt.
gitlab A 10.3.190.62
ns1 A 10.3.190.60
ns2 A 10.3.190.61
/etc/named/zones/db.10.3
$ORIGIN .
$TTL 3600 ; 1 hour
3.10.in-add.arpa IN SOA ns1.sis.trt. admin.sys.trt. (
2019112001 ; serial
600 ; refresh (10 minutes)
300 ; retry (5 minutes)
3600 ; expire (1 hour)
3600 ; minimum (1 hour)
)
NS ns1.sis.trt.
NS ns2.sis.trt.
$ORIGIN 190.3.10.in-add.arpa.
60 PTR ns1.sis.trt.
61 PTR ns2.sis.trt.
62 PTR gitlab.sis.trt.
My master dns configuration
The master is offline so I can't post any information. I'll add this information as soon as I have the server back. But it's a slave problem and the synchronized files are ok (as I remember the server zone files).