Connecting to RDS database from EC2 instance using bind9 CNAME alias
- by mptre
I'm trying to get internal DNS up and running on a EC2 instance. The main goal is to be able to define CNAME aliases for other AWS services. For example: Instead of using the RDS endpoint, which might change over time, an alias mysql.company.int can be used instead.
I'm using bind9 and here's my config files:
/etc/bind/named.conf.local
zone "company.int" {
type master;
file "/etc/bind/db.company.int";
};
/etc/bind/db.company.int
;
$TTL 3600
@ IN SOA company.int. company.localhost. (
20120617 ; Serial
604800 ; Refresh
86400 ; Retry
2419200 ; Expire
604800 ) ; Negative Cache TTL
;
@ IN NS company.int.
@ IN A 127.0.0.1
@ IN AAAA ::1
; CNAME
mysql IN CNAME xxxx.eu-west-1.rds.amazonaws.com.
The dig command ensures me my alias is working as excepted:
$ dig mysql.company.int
...
;; ANSWER SECTION:
mysql.company.int. 3600 IN CNAME xxxx.eu-west-1.rds.amazonaws.com.
xxxx.eu-west-1.rds.amazonaws.com. 60 IN CNAME ec2-yyy-yy-yy-yyy.eu-west-1.compute.amazonaws.com.
ec2-yyy-yy-yy-yyy.eu-west-1.compute.amazonaws.com. 589575 IN A zzz.zz.zz.zzz
...
As far as I can understand a reverse zone isn't needed for a simple CNAME alias. However when I try to connect to MySQL using my newly created alias the operation is giving me a timeout.
$ mysql -uuser -ppassword -hmysql.company.int
ERROR 2003 (HY000): Can't connect to MySQL server on 'mysql.company.int' (110)
Any ideas? Thanks in advantage!
