Table of Contents
Networking - DNS - Bind - Enable Logging
The rndc command controls the operation of a name server.
If rndc is invoked with no command line options or arguments, it prints a short summary of the supported commands and the available options and their arguments.
rndc communicates with the name server over a TCP connection, sending commands authenticated with digital signatures.
In the current versions of rndc and bind the only supported authentication algorithm is HMAC-MD5, which uses a shared secret on each end of the connection. This provides TSIG-style authentication for the command request and the name server's response.
All commands sent over the channel must be signed by a key_id known to the server.
Turn on logging
Type the following command as root to toggle query logging:
rndc querylog
View bind sever query log
Once this is done, you can view all logged queries usimg /var/log/messages file.
To view those queries, type:
tail -f /var/log/messages
You might need to tail /var/log/syslog instead of /var/log/messages.
Turn off logging
Type the following command as root to toggle query logging:
rndc querylog
NOTE: It is important to place all log files into /var/log/named.
The reason for this is that AppArmor by default only allows this location in /var/log.
If you for instance used an alternative path, say /var/log/bind for the log files then you need to update AppArmor.
vi /etc/apparmor.d/usr.sbin.named
Create the logging master file.
vi /etc/bind/named.conf.logging
and populate as:
- /etc/bind/named.conf.logging
logging { channel default_file { file "/var/log/named/default.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel general_file { file "/var/log/named/general.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel database_file { file "/var/log/named/database.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel security_file { file "/var/log/named/security.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel config_file { file "/var/log/named/config.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel resolver_file { file "/var/log/named/resolver.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel xfer-in_file { file "/var/log/named/xfer-in.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel xfer-out_file { file "/var/log/named/xfer-out.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel notify_file { file "/var/log/named/notify.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel client_file { file "/var/log/named/client.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel unmatched_file { file "/var/log/named/unmatched.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel queries_file { file "/var/log/named/queries.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel network_file { file "/var/log/named/network.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel update_file { file "/var/log/named/update.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel dispatch_file { file "/var/log/named/dispatch.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel dnssec_file { file "/var/log/named/dnssec.log" versions 3 size 5m; severity dynamic; print-time yes; }; channel lame-servers_file { file "/var/log/named/lame-servers.log" versions 3 size 5m; severity dynamic; print-time yes; }; category default { default_file; }; category general { general_file; }; category database { database_file; }; category security { security_file; }; category config { config_file; }; category resolver { resolver_file; }; category xfer-in { xfer-in_file; }; category xfer-out { xfer-out_file; }; category notify { notify_file; }; category client { client_file; }; category unmatched { unmatched_file; }; category queries { queries_file; }; category network { network_file; }; category update { update_file; }; category dispatch { dispatch_file; }; category dnssec { dnssec_file; }; category lame-servers { lame-servers_file; }; };
Make the logging master file accessible to bind:
chown root.bind /etc/bind/named.conf.logging
and set the permissions on the file:
chmod 640 /etc/bind/named.conf.logging
Add the logging master file into the bind config.
vi /etc/bind/named.conf>
and modify as:
- /etc/bind/named.conf
include "/etc/bind/named.conf.logging"; include "/etc/bind/named.conf.options"; include "/etc/bind/named.conf.local";
It is advisable to create the log files manually:
touch /var/log/named/querylog.log touch /var/log/named/general.log touch /var/log/named/database.log touch /var/log/named/security.log touch /var/log/named/config.log touch /var/log/named/resolver.log touch /var/log/named/xfer-in.log touch /var/log/named/xfer-out.log touch /var/log/named/notify.log touch /var/log/named/client.log touch /var/log/named/unmatched.log touch /var/log/named/queries.log touch /var/log/named/network.log touch /var/log/named/update.log touch /var/log/named/dispatch.log touch /var/log/named/dnssec.log touch /var/log/named/lame-servers.log
Make the files accessible to bind:
chown bind.bind /var/log/named/*
Make the log files writeable:
chmod 600 /var/log/named/*
Restart bind server to apply changes
systemctl restart bind.service
Check that bind is running okay
systemctl status bind.service