Your outside interface should be dhcp client
interface Vlan10
nameif outside
security-level 0
ip address dhcp setroute
Your inside interface ip address
interface Vlan20
nameif inside
security-level 100
ip address cyruslab.local 255.255.255.0
dhcp auto_config should be enabled globally
dhcpd auto_config outside
Result:
**auto-config from interface ‘outside’
**auto_config dns 218.186.1.38 202.156.1.58
autoconfig helps your asa to get the dns, wins information obtained from your isp dhcp server.
PAT
nat (inside) 1 192.168.20.0 255.255.255.0 dns
global (outside) 1 interface
Enable dns lookup
dns domain-lookup outside
Optional: Set a valid dns server on your asa
dns name-server 8.8.8.8
Result:
cyrus(config)# ping http://www.google.com
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 74.125.235.16, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 10/12/20 ms
Set ntp server
ntp server 202.186.13.232
(from pool.ntp.org)
Set timezone
clock timezone SGT 8
cyruslab 