Unable to start the named service
 

vim /etc/named.conf

options {
listen-on port 53 { 127.0.0.1; 192.168.1.162; };
listen-on-v6 port 53 { ::1; 192.168.1.162; };
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 { localhost; 192.168.1.0/24; };
allow-transfer { localhost; 192.168.1.162; };
recursion no;

dnssec-enable yes;
dnssec-validation yes;
dnssec-lookaside auto;

/* 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";
};
zone"arun.com" IN {
type master;
file "/var/named/arun.com.for";
allow-update { none; };
};

include "/var/named/arun.com.for";
..................................................................

vim /var/named/arun.com.for

$TTL 86400
arun.com. IN SOA www.arun.com. root.arun.com. (
2013042201
3600
1800
604800
86400
)
arun.com. IN NS www.arun.com.
www IN A 192.168.1.162

........................................................

service named start


Starting named:
Error in named configuration:
/var/named/arun.com.for:1: unknown option '$TTL'
/etc/named.conf:51: unexpected token near end of file
[FAILED]
..............................................

plz help me solve this problem

Spell out your words, please. And did you read/understand the error message? It's VERY clear, and tells you exactly where the syntax error in your file is. Correct the bad syntax in the configuration file, and read the documentation and see examples:
http://www.tldp.org/HOWTO/DNS-HOWTO-7.html
http://www.zytrax.com/books/dns/apa/ttl.html