How to configure rndc key with chrooted bind on linux?

Environment : RHEL 6.1 .

Here are the steps that I followed :

1. vi /etc/rndc.conf and following line

----
options {
default-server 127.0.0.1;
default-key "rndckey";
};

server 127.0.0.1 {
key "rndckey";
};

key "rndckey" {
algorithm "hmac-md5";
secret "secret key will be placed here";
};
---

2. cd /var/named/chroot/etc/

3. $dnssec-keygen -r /dev/urandom -a HMAC-MD5 -b 256 -n HOST rndc
4. cat *.private
5. copy the key from private file and put it in /etc/rndc.conf at "secret" line.
6. Do link :

$ln -s /var/named/chroot/etc/rndc.conf /etc/rndc.conf

7. vi /etc/named.conf put following :

----
controls {
inet 127.0.0.1 allow { 127.0.0.1; } keys { rndckey; };
};

key "rndckey" {
algorithm "hmac-md5";
secret "replace_keyhere";
};

----

8. Restart named and check status :

$rndc status

Output will look like :

$rndc status
version: 9.7.3-P3-RedHat-9.7.3-2.el6_1.P3.2
CPUs found: 1
worker threads: 1
number of zones: 20
debug level: 0
xfers running: 0
xfers deferred: 0
soa queries in progress: 0
query logging is OFF
recursive clients: 0/0/1000
tcp clients: 0/100
server is up and running

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How to rotate sudo log?

Scenario : Sudo log files will keep the activities of sudo users and their login status in /var/log/sudolog.

Tested platform : RHEL 5

Solution :

1. Create a sudo log file and put it in /etc/sudoers. Then rotate it for 90 days. As an example :

$touch /var/log/sudolog

2. vi /etc/sudoers and add following lines :

-----
Defaults !syslog
Defaults logfile = /var/log/sudolog
-----

Then save it.

3. Rotating this log file :

vi /etc/logrotate.d/sudolog and put following :

------
/var/log/sudolog {
rotate 90
size 5M
postrotate
/usr/bin/killall -HUP syslogd
endscript
}
------

4. Now restart syslogd :

$service syslogd restart

This will keep maximum 5MB file of 90 different copies. Old copy will be removed first.

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