CCNA Access List Sim 2
Question
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 the 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.
The task is to create and apply a numbered access-list with no more than three statements that will allow ONLY host C web access to the Finance Web Server. No other 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 servers in the Server 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.
The Public Web Server is assigned an IP address of 172.22.242.17
Answer and Explanation
(Note: If you are not sure how to use access-list, please check out my access-list tutorial at: http://www.9tut.com/access-list-tutorial, also some modifications about the access-list have been reported so you should read the “Some modifications” section at the end of this question to understand more. You can also download this sim to practice (open with Packet Tracer) here: http://www.9tut.com/download/9tut.com_Access-list_sim2.pkt
Corp1>enable (you may enter “cisco” as it passwords here)
We should create an access-list and apply it to the interface which is connected to the Server LAN because it can filter out traffic from both Sw-2 and Core networks. The Server LAN network has been assigned addresses of 172.22.242.17 – 172.22.242.30 so we can guess the interface connected to them has an IP address of 172.22.242.30 (.30 is the number shown in the figure). Use the “show running-config” command to check which interface has the IP address of 172.22.242.30.
Corp1#show running-config
We learn that interface FastEthernet0/1 is the interface connected to Server LAN network. It is the interface we will apply our access-list (for outbound direction).
Corp1#configure terminal
Our access-list needs to allow host C – 192.168.33.3 to the Finance Web Server 172.22.242.23 via web (port 80)
Corp1(config)#access-list 100 permit tcp host 192.168.33.3 host 172.22.242.23 eq 80
Deny other hosts access to the Finance Web Server via web
Corp1(config)#access-list 100 deny tcp any host 172.22.242.23 eq 80
All other traffic is permitted
Corp1(config)#access-list 100 permit ip any any
Apply this access-list to Fa0/1 interface (outbound direction)
Corp1(config)#interface fa0/1
Corp1(config-if)#ip access-group 100 out
Notice: We have to apply the access-list to Fa0/1 interface (not Fa0/0 interface) so that the access-list can filter traffic coming from both the LAN and the Core networks. If we apply access list to the inbound interface we can only filter traffic from the LAN network.
In the real exam, just click on host C and open its web browser. In the address box type http://172.22.242.23 to check if you are allowed to access Finance Web Server or not. If your configuration is correct then you can access it.
Click on other hosts (A, B and D) and check to make sure you can’t access Finance Web Server from these hosts.
Finally, save the configuration
Corp1(config-if)#end
Corp1#copy running-config startup-config
(This configuration only prevents hosts from accessing Finance Web Server via web but if this server supports other traffic – like FTP, SMTP… then other hosts can access it, too.)
Notice: In the real exam, you might be asked to allow other host (A, B or D) to access the Finance Web Server so please read the requirement carefully.
Some modifications:
Modification 1:
| permit host B from accessing finance server | access-list 100 permit ip host 192.168.33.2 host 172.22.242.23 |
| deny host B from accessing other servers (not the whole network) | access-list 100 deny ip host 192.168.33.2 172.22.242.16 0.0.0.15 |
| permit everything else | access-list 100 permit ip any any |
Modification 2:
| Only allow Host C to to access the financial server | access-list 100 permit ip host 192.168.33.3 host 172.22.242.23 |
| Not allow anyone else in any way communicate with the financial server | access-list 100 deny ip any host 172.22.242.23 |
| Allow all other traffic | access-list 100 permit ip any any |
Modification 3:
| - Host C should be able to use a web browser(HTTP)to access the Finance Web Server | access-list 100 permit tcp host 192.168.33.3 host 172.22.242.23 eq 80 |
| - Other types of access from host C to the Finance Web Server should be blocked - All access from hosts in the Core or local LAN to the Finance Web Server should be blocked |
access-list 100 deny ip any host 172.22.242.23 (because the requirement says we can not use more than 3 statements so we have to use “any” here for the hosts in the Core and hosts in local LAN) |
| - All hosts in the Core and local LAN should be able to access the Public Web Server * | access-list 100 permit ip any host (If the question asks this, surely it has to give you the IP of Public Web Server) but in the exam you should use “access-list 100 permit ip any any” |
Modification 4:
| Host C should be able to use a web browser to access the financial web server | access-list 100 permit tcp host 192.168.33.3 host 172.22.242.23 eq 80 |
| Other types of access from host C to the finance web server should be blocked | access-list 100 deny ip host 192.168.33.3 host 172.22.242.23 |
| All hosts in the core and on the local LAN should be able to access the Public web server * | access-list 100 permit ip any host (The IP of Public Web Server will surely be given in this question) but in the exam you should use “access-list 100 permit ip any any” |
* There are some reports about the command of “All hosts in the core and on the local LAN should be able to access the Public web server” saying that the correct command should be “access-list 100 permit ip any any”, not “access-list 100 permit ip any host (IP of Public Web Server)”. Although I believe the second command is better but maybe you should use the first command “access-list 100 permit ip any any” instead as some reports said they got 100% when using this command (even if the question gives you the IP address of Public Web Server). It is a bug in this sim.
(Note: Don’t forget to apply this access list to the suitable interface or you will lose points
interface fa0/1
ip access-group 100 out
And in the exam, they may slightly change the requirements, for example host A, host B instead of host C… so make sure you read the requirement carefully and use the access-list correctly)
I created this sim in Packet Tracer v5.2.1 so you can practice with it. You will need new version of Packet Tracer to open it (v5.1+).
Download this sim here
Notice: After typing the commands above, if you make a “ping” from other hosts (PC0, PC1, PC3) then PC4 (Finance Web Server) can still reply because we just filter HTTP traffic, not ICMP traffic. To generate HTTP traffic, select “Web Browser” in the “Desktop” tab of these PCs. When a web browser opens, type the IP address of Finance Web Server and you can see how traffic flows in Simulation Mode.
And notice that in the initial configuration of this sim the Core network can ping Finance Web Server. We have to create an access-list that can filter this traffic too.
Other lab-sims on this site:
Yes Jules,
the same way to find out IPs for Finance or Web server.
Hello PK,
copy run st is the standard command , don’t even try using wr?
@ Abdullah:
access-list 100 permit tcp host– used when u access the web browser
access-list 100 permit ip host– used when u access the server
some one correct me if im wrong
hello Adullah,
tcp, udp or ip are used to specify protocol type.
If you are permitting/denying a specific protocol, we can use either tcp or udp , for eg. web browsing = http= 80, we use tcp cz http is a tcp type. other tcp types are: http, ftp, telnet, ssh. but it can also be a udp type such as snmp, dns etc
If you are pemitting/denying any other non-specific access , use ip
anybody knows a good site for A+ exam practice questions ?
Passed my ccna exam today 1000/1000 Eigrp y access list 2 simulations, Gillbeast, Watson and 9tut. Thank you so much 9tut
Passed today with 986 score! Thanks to 9tut.
@Dany, thanks for reply. I used “copy run st”.
Hi 9 tut
today got follow qustions in ACL LAB
Host B needs to access Finance web server via www
All other type of access from host b shot b block
block other hosts to access to finance web server should
Core network and lan should access other server
@dany, i just have a question, what do you mean about them not providing any hosts IP addresses? you mean even the network address, they dont provide and we still need to look for it thru show run? anway, thanks in advance
what do you mean by testing our subletting/subnetting knowledge? do we still have to configure the interface and look for the subnet it belongs?
@Dany, may you explaine how could we know the servers IP ? they did not have .17 / .30 .. thanks :)
passed today with 972/1000 watson and 9tut dumps 100% valid + acl1 + acl2 mod3 + eigrp tshoot from 9tut … thanx 9tut
Hello Ann,
If they don’t provide .17 or .30, the game will be easy cz
They should give you either:
1. Access to the servers/PCs and you can view the IP by click on specif host/server and then click on: Config
2. info on each specif host /server IP address
Kylie,
I meant Subnetting cz if you don’t know subnetting , then how can you determine the next hop address from local address?
Remember : directly connected interfaces always belong to the same subn/w.
The mask will be your determining factor in this case.
cisco clearly mentions each n every ip of each host and servers….dont worry guyz……
On the mods 3 and 4, I think the last line: “access-list 100 permit ip any any” is correct because if otherway we permit only the public web server, it will not work without the DNS server, even for the web sevices on the financial server.
hi guys, where can i find the ACL 1? thank you
got this LAB on my test CCNA 23.10.2014
+ ACL
+ EIGRP
passed the test woth 849.
thanks to 9tut.
wow congratz. vitafed76
I hope I can make it too.. on nov 21
any tips aside from studying hard
hows the eigrp lab ?
hi guys,
im kinda confused in mod 1
deny host B from accessing other servers (not the whole network)–access-list 100 deny ip host 192.168.33.2 172.22.242.16 0.0.0.15
based on my understanding when you are referring to permit/deny a whole network It should like this (172.22.242.16 0.0.0.15)
or I guess someone give me an example of denying the whole network and not the whole network
thanks guys
Important News…
Dumps changed yesterday….i took ccna yesterday and i got failed in that exam.
Almost the whole pool of questions were different.
The labs which i had were.
VTP(total 11 ques)
ACL 2(slight variations but new scenario)
RIPV2
NAT PAT 2(similar to the one given in 9tut).
Ccna is total waste of money
hi
johnson can you gime me more information plz
I’m taking the exam tomorrow. I’ll update you guys harhar
@angy
I took ccna yesterday…..n i got failed…….
The questions were new and haven’t seen almost all of them…
I was preparing for ccna from last 3 months….
But it ends worst for me…..:’-(
@johnson
but some people have successfully passed yesterday
questions were old
Passed the CCNA 200-120. Three simulation ACL, ACL2 slightly different and EIGRP AS number change also slightly different would say bit tricky if you do not run show IP route on each router you wont find out the trick. Suggesting you go and run Show Run on every router and figure out the mistakes. All the best brother.
@Shahriar When you passed? Today? Was any difference in the questions?
@Shahriar what was the difference?
I have the exam tomorrow. Can someone else confirm that dumps and labs have changed please ??
Yes they are changed…
All the ques are new and unseen before……:’-(
Could someone has been confirm the exam pool questions were changed recently ???other than Johnson???? >> i strongly believe 9tut will crack for the updated exam question and lab pattern??
Please can someone confirm if the exam pool has changed taking mine on the 13th
Tomorrow is my examen, and the questions are changed???? Please no!!!
I had this one today… Pass with 934
thanks a lot 9tut!!! need nothing else that 9tut thx once again
i have given my exam today scored 945, all same question but little changes in lab-ip’s ,eigrp sim (ip’s changed) ACL-1 has it is. ACL-2 tips changed( modification 3) asked, host b.
sorry ips* change
:*
Am taking my exam next week
. Any changes with the labs?
Passed exam today. 945/1000
Labs: ACL, ACL 2, EIGRP Lab.
Dumps: Watson.314q and GillBeast.299q
No one new questions. All from dumps.
I don’t know about other counties but in Russia dumps still valid.
Good luck guys :)
@Alex thank for ur feedback,
my exam tmwr wish me luck guys
oh my goodness. the exam change??? how bout the questions? is it still the same here in 9tut?? im worried now for my exam. :(
so that means if the exam changed. the dumps that were circulating are useless now ??
Passed UK, dumps and labs still valid. Remember in this sim you cant use “ip access-list extended” it must be the old “access-list 100″ command.
james…go and sleep..
@holman: thanks for that :D
i passed today
with 945 marks