Mattias:
Cisco routers have the ability to log event messages to a console port, a local buffer stored in NVRAM, a syslog server, or to an SNMP server running on a remote NMS station.
Console logging is automatically enabled, but logging messages can only be viewed by a terminal that is directly connected to the console port, unless the terminal monitor command is issued at the Router# prompt during a telnet session.
To enable logging on a router you can use the following commands or customize them for your purposes:
Router(config)# logging on
(enables logging to non-console connections)
Router(config)# logging source-interface loopback0
(sources logging traffic to the loopback interface)
Router(config)# logging buffered 16000
(enables logging to local NVRAM and sets log size to 16K bytes)
Router(config)# logging host
(Repeat for multiple syslog servers)
Router(config)# logging origin-id hostname
(Tells router to include its hostname when sending log messages to a syslog server)
Then you ask:
Please explain the following lines for me:
logging facility syslog
This is a command that is typically used with UNIX-based syslog servers. Most UNIX servers expect syslog messages to arrive with a facility id of 20.
logging source-interface VlanXX
This command tells the network device to place a particular interface's IP address in the source-address field of the IP datagram. Remember that the logging traffic is created by the router itself, so it has to select a source IP address. If you don't specify which source address to use, it will automatically select the interface address of the interface from which the logging traffic exits.
"I tried to make an access-list but the switch converted 192.168.30.250 to 0.0.0.250 after saving config. How come?
access-list 103 permit tcp 0.0.0.250 255.255.255.0 0.0.0.40 255.255.255.0 eq cmd"
Why do you want to create an access-list? You dont need it at all. By default, an interface allows all traffic in and out. Once you apply an access-list to an interface, it will permit or deny traffic according to its rules.
The reason the router changed the structure of the access list in the way it did was that you configured it incorrectly. What I bet you did was use a subnet mask instead of a wildcard mask.
This is the correct syntax for an IP access list:
access-list access-list-number [dynamic dynamic-name [timeout minutes]]
{deny | permit} protocol source source-wildcard
destination destination-wildcard [precedence precedence]
[tos tos] [log | log-input] [time-range time-range-name]
HTH
If so, please rate my post.
Victor
