Exam 200-105 topic 1 question 140 discussion

SIMULATION -

Lab -Access List Simulation -
A network associate is adding security to the configuration of the Corp1 router. The user on host C should be able to use a web browser to access financial information from the Finance Web Server. No other hosts from the LAN nor Core should be able to use a web browser to access this server. Since there are multiple resources for the corporation at this location including other resources on the Finance Web Server, all other traffic should be allowed. is to create and apply an access-list with no more than three statements that will allow ONI Y host C web access to the Finance Web Server. No other

The task -
hosts will have web access to the Finance Web Server. All other traffic is permitted.
Access to the router CLI can be gained by clicking on the appropriate host.
All passwords have been temporarily set to "cisco".
The Core connection uses an IP address of 198.18.196.65
The computers in the Hosts LAN have been assigned addresses of 192.168.33.1 192.168.33.254.
✑ host A 192.168.33.1
✑ host B 192.168.33.2
✑ host C 192.168.33.3
✑ host D 192.168.33.4
The computers in the Hosts LAN have been assigned addresses of 172.22.242.17 172.22.242.30
The Finance Web Server is assigned an IP address of 172.22.242.23

Suggested Answer: See explanation


Select the console on Corp1 router

Configuring ACL -

Corp1>enable -

Corp1#configure terminal -
Comment: To permit only Host C (192. 168. 33. 3){source addr} to access finance server address (172. 22.242. 23){destination addr} on port number 80(web)
Corp1(config)# access-list 100 permit tcp host 192.168.33.3 host 172.22.242.23 eq 80
Comment: To deny any source to access finance server address (172. 22. 242. 23) {destination addr} on port number 80 (web)
Corp1(config)# access-list 100 deny tcp any host 172.22.242.23 eq 80
Comment:
To permit ip protocol from any source to access any destination because of the implicit deny any any statement at the end of ACL.
Corp1(config)# access-list 100 permit ip any any
Applying the ACL on the Interface
Comment: Check show ip interface brief command to identify the interface type and number by checking the IP address configured.

Corp1(config)#interface fa 0/1 -
If the ip address configured already is incorrect as well as the subnet mask. this should be corrected in order ACL to work type this commands at interface mode: no ip address 192. x. x. x 255. x. x. x (removes incorrect configured ip address and subnet mask) Configure correct IP Address and subnet mask: ip address 172. 22. 242. 30 255. 255. 255. 24
0 (range of address specified going to server is given as 172. 22. 242. 17 172. 22. 242. 30)
Comment: Place the ACL to check for packets going outside the interface towards the finance web server.
Corp1(config-if)#ip access-group 100 out

Corp1(config-if)#end -
Important: To save your running config to startup before exit.
Corp1#copy running-config startup-config
Verifying the Configuration:
Step1: Show ip interface brief command identifies the interface on which to apply access list.
Step2: Click on each host A, B, C & D. Host opens a web browser page, select address box of the web browser and type the ip address of finance web server
(172. 22. 242. 23) to test whether it permits /deny access to the finance web Server.