Solved: Re: ACL PROBLEM

Didier1966 · ‎11-29-2010

Hello,

I have a CISCO 1841 ROUTER (IP=192.168.1.250) and a CATALYST 2950 SWITCH (IP=192.168.1.251) in my test LAB.

Both are connected with a TRUNK , to share the same VLANS.

The problem is , when I connect to VLAN 10 or 20 or 30 , I am not able to PING the ROUTER or the SWITCH , this give me a problem to save the files to my TFTP server.

When I connect to F0/1 , I receive the right IP ADDRESS 192.168.10.x

When I connect to F0/2 , I receive the right IP ADDRESS 192.168.20.x

When I connect to F0/3 , I receive the right IP ADDRESS 192.168.30.x

ON ALL OF THEM I HAVE INTERNET

I am really new on the CISCO stuff ,but I studying a lot

Here bellow I give you a copy of the router config and the switch config :

SWITCH:

interface FastEthernet0/1

switchport access vlan 10

switchport mode access

!

interface FastEthernet0/2

switchport access vlan 20

switchport mode access

!

interface FastEthernet0/3

switchport access vlan 30

switchport mode access

interface FastEthernet0/12

switchport mode trunk

!

interface Vlan1

ip address 192.168.1.251 255.255.255.0

no ip route-cache

ROUTER:

interface FastEthernet0/0/0

switchport access vlan 10

spanning-tree portfast

!

interface FastEthernet0/0/1

switchport access vlan 20

spanning-tree portfast

!

interface FastEthernet0/0/2

switchport access vlan 30

spanning-tree portfast

!

interface FastEthernet0/0/3

switchport mode trunk

!

interface Vlan1

ip address 192.168.1.250 255.255.255.0

!

interface Vlan10

ip address 192.168.10.1 255.255.255.0

ip access-group 102 out

ip nat inside

ip virtual-reassembly

!

interface Vlan20

ip address 192.168.20.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

interface Vlan30

ip address 192.168.30.1 255.255.255.0

ip nat inside

ip virtual-reassembly

ip http server

ip http authentication local

ip http secure-server

ip dns server

ip nat inside source list 101 interface FastEthernet0/0 overload

ip nat inside source static tcp 192.168.100.10 80 81.164.200.35 8095 extendable

!

access-list 101 permit ip 192.168.10.0 0.0.0.255 any

access-list 101 permit ip 192.168.20.0 0.0.0.255 any

access-list 101 permit ip 192.168.30.0 0.0.0.255 any

access-list 101 permit ip 192.168.100.0 0.0.0.255 any

access-list 102 permit ip any any

no cdp run

!

I DO NOT KNOW IF THIS IS HELPFUL FOR THIS PROBLEM , BUT HERE YOU HAVE THE VTP :

ROUTER VTP :

ROUTER1841#sh vtp st

VTP Version : 2

Configuration Revision : 12

Maximum VLANs supported locally : 19

Number of existing VLANs : 8

VTP Operating Mode : Server

VTP Domain Name : DRI

VTP Pruning Mode : Disabled

VTP V2 Mode : Disabled

VTP Traps Generation : Disabled

MD5 digest : 0x4C 0x8D 0x3C 0x87 0x0A 0x11 0xFA 0xC7

Configuration last modified by 192.168.1.250 at 11-29-10 18:57:03

Local updater ID is 192.168.1.250 on interface Vl1 (lowest numbered VLAN interface found)

SWITCH VTP:

SWITCH2950-12#sh vtp status

VTP Version : 2

Configuration Revision : 12

Maximum VLANs supported locally : 128

Number of existing VLANs : 8

VTP Operating Mode : Client

VTP Domain Name : DRI

VTP Pruning Mode : Disabled

VTP V2 Mode : Disabled

VTP Traps Generation : Disabled

MD5 digest : 0x4C 0x8D 0x3C 0x87 0x0A 0x11 0xFA 0xC7

Configuration last modified by 192.168.1.250 at 11-29-10 18:57:03

Thank You In Advance AGAIN for your help

Best Regards,

Didier

Richard Burts · ‎11-29-2010

Didier

You show us only part of the router confg and that makes it difficult to understand some of what is going on. For example you show us several interfaces configured with ip nat inside, but show nothing that is ip nat outside.

You also do not show us anything about the routing logic on the router. And you do not tell us where the TFTP server is located.

There is also some inconsistency that puzzles me. You show ip nat inside on vlan10, and vlan20 and vlan 30 but not on vlan 1. Is there a reason for that?

Even though there are many things that we do not know which would be helpful, I am going to make a guess at the problem. I guess that the problem has to do with address translation and with the fact that the access list which identifies traffic to be translated (access list 101) permits all traffic from networks 192.168.10.0, 192.168.20.0, 192.168.30.0, and 192.168.100.0 to any destination to be translated. I guess that if you re-write the access list and first deny traffic from these networks to the network of the TFTP server and then permits the networks to any destination that your problem may be solved.

Give this a try and let us know what happens.

HTH

Rick

HTH

Rick

View solution in original post

Richard Burts · ‎11-30-2010

Didier

I wish that it were completely normal to post to the forum when you find a solution to a problem. But my experience is that not everyone does this. And I agree with you that this results in time being wasted.

There is confusion about the button that I refer to as solved. Perhaps now it says answered or something like that. But in my post there is a green check mark on a yellow background which is the indication that the response answered (or solved) the issue. The original poster is the only one who can give that mark, and it looks like you did. The check mark shows up in the listing of the discussions (when you have logged in to the forum) and is the indicator to other readers that the issue is answered (or solved).

HTH

Rick

HTH

Rick

View solution in original post

tomscookin · ‎11-29-2010

Isolate this down just a bit. Pick 1 single port to connect your PC to, and troubleshoot starting from there.

For example, plug in to the vlan10 port (f0/1) ... and try to ping the vlan10 ip address of the router: 192.168.10.1

Does this work? If so, then that address should be your default gateway on the pc ... Is it? If so, then you should also be able to ping the other IP addresses from that port.

The router/switch "ips" are on vlan 1 ... which is different than what you are putting your PC on, so your gateway address must be a device that can route you to the destination vlan.

cadet alain · ‎11-29-2010

Can you be a little bit clearer which ip can't you ping from which ip?

Regards.

Don't forget to rate helpful posts.

Richard Burts · ‎11-29-2010

Didier

You show us only part of the router confg and that makes it difficult to understand some of what is going on. For example you show us several interfaces configured with ip nat inside, but show nothing that is ip nat outside.

You also do not show us anything about the routing logic on the router. And you do not tell us where the TFTP server is located.

There is also some inconsistency that puzzles me. You show ip nat inside on vlan10, and vlan20 and vlan 30 but not on vlan 1. Is there a reason for that?

Even though there are many things that we do not know which would be helpful, I am going to make a guess at the problem. I guess that the problem has to do with address translation and with the fact that the access list which identifies traffic to be translated (access list 101) permits all traffic from networks 192.168.10.0, 192.168.20.0, 192.168.30.0, and 192.168.100.0 to any destination to be translated. I guess that if you re-write the access list and first deny traffic from these networks to the network of the TFTP server and then permits the networks to any destination that your problem may be solved.

Give this a try and let us know what happens.

HTH

Rick

HTH

Rick

Didier1966 · ‎11-29-2010

Hello All,

Thank you for your prompt reaction

Sorry if I was not clear enough , but bellow you have the FULL WORKING ROUTER configuration.

When I connect my computer that is ALSO the TFTP SERVER (just for upload and download) , I receive :

On F0/0/0 = 192.168.10.x PING 192.168.10.1 is OK

On F0/0/2 = 192.168.20.x PING 192.168.20.1 is OK

On F0/0/3 = 192.168.30.x PING 192.168.30.1 is OK

F0/0/4 is the TRUNK to the SWITCH

The ROUTER has a IP 192.168.1.250

The SWITCH has a IP 192.168.1.251

From IN IOS I can PING : 192.168.1.250 and 192.168.1.251

But from one of the 3 VLANS (192.168.10.x or 192.168.20.x or 192.168.30.x) the ping does not work , so I presume something is wrong in my ACL ?!?

NOTE : I DO NOT NEED TO HAVE ACCES FROM ALL , IF I HAVE ACCES FROM ONE IT IS OK, I just need to have access to copy the file from my SWITCH to my COMPUTER (TFTP SERVER)

Thank You Again for your help. I hope that one day I will understand how the logic of ACL works

!

! Last configuration change at 21:02:50 gmt+1 Mon Nov 29 2010 by admin

! NVRAM config last updated at 23:06:14 gmt+1 Mon Nov 29 2010 by admin

!

version 12.4

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname ROUTER1841

!

boot-start-marker

boot-end-marker

!

logging buffered 51200 warnings

enable password 7 05080F1C2243

!

aaa new-model

!

aaa authentication banner

THIS SYSTEM IS SOLELY FOR USE OF AUTHORISED USERS FOR OFFICIAL PURPOSES

!

aaa session-id common

clock timezone gmt+1 1

clock summer-time gmt+2 recurring last Sun Mar 2:00 last Sun Oct 3:00

dot11 syslog

no ip source-route

ip cef

!

no ip dhcp use vrf connected

ip dhcp excluded-address 192.168.10.1

ip dhcp excluded-address 192.168.20.1

ip dhcp excluded-address 192.168.30.1

ip dhcp excluded-address 192.168.100.1

!

ip dhcp pool vlan10

import all

network 192.168.10.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.10.1

lease 5

!

ip dhcp pool vlan20

import all

network 192.168.20.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.20.1

lease 5

!

ip dhcp pool vlan30

network 192.168.30.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.30.1

!

ip dhcp pool FIX-IP

host 192.168.100.66 255.255.255.0

client-identifier 0100.089b.ad17.8f

client-name FIX-IP

!

ip dhcp pool TEST

host 192.168.100.20 255.255.255.0

client-identifier 0100.2241.353f.5e

!

ip dhcp pool internal

network 192.168.100.0 255.255.255.0

dns-server 192.168.100.1

default-router 192.168.100.1

!

no ip bootp server

ip domain name dri

ip ddns update method DynDNS

HTTP

add http://dri66:@members.dyndns.org/nic/update?system=dyndns&hostname=cisco1841.dyndns.info&myip=

interval maximum 1 0 0 0

interval minimum 1 0 0 0

!

multilink bundle-name authenticated

!

username Admin privilege 15 secret 5 $1$gAFQ$2ecAHSYEU9

archive

log config

hidekeys

!

ip ssh time-out 60

ip ssh authentication-retries 2

ip ssh port 8096 rotary 1

ip ssh version 2

!

interface FastEthernet0/0

description DMZ

ip ddns update hostname cisco1841.dyndns.info

ip ddns update DynDNS

ip address dhcp

no ip unreachables

no ip proxy-arp

ip nat outside

ip virtual-reassembly

duplex auto

speed auto

!

interface FastEthernet0/1

description INTERNAL$ETH-LAN$

ip address 192.168.100.1 255.255.255.0

no ip proxy-arp

ip nat inside

ip virtual-reassembly

duplex auto

speed auto

!

interface FastEthernet0/0/0

switchport access vlan 10

spanning-tree portfast

!

interface FastEthernet0/0/1

switchport access vlan 20

spanning-tree portfast

!

interface FastEthernet0/0/2

switchport access vlan 30

spanning-tree portfast

!

interface FastEthernet0/0/3

switchport mode trunk

!

interface Vlan1

ip address 192.168.1.250 255.255.255.0

!

interface Vlan10

ip address 192.168.10.1 255.255.255.0

ip access-group 102 out

ip nat inside

ip virtual-reassembly

!

interface Vlan20

ip address 192.168.20.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

interface Vlan30

ip address 192.168.30.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

ip forward-protocol nd

!

ip http server

ip http authentication local

ip http secure-server

ip dns server

ip nat inside source list 101 interface FastEthernet0/0 overload

ip nat inside source static tcp 192.168.100.10 80 81.164.200.35 8095 extendable

!

access-list 101 permit ip 192.168.10.0 0.0.0.255 any

access-list 101 permit ip 192.168.20.0 0.0.0.255 any

access-list 101 permit ip 192.168.30.0 0.0.0.255 any

access-list 101 permit ip 192.168.100.0 0.0.0.255 any

access-list 102 permit ip any any

no cdp run

!

control-plane

!

banner exec

WELCOME YOU ARE NOW LOGED IN

banner login

WARNING !!!

IF YOU ARE NOT :

Didier Ribbens

Please Leave NOW !!!

YOUR IP and MAC address will be LOGGED !!!

!

line con 0

speed 115200

line aux 0

line vty 0 4

access-class 5 in

privilege level 15

rotary 1

transport input telnet ssh

line vty 5 15

access-class 5 in

rotary 1

!

scheduler allocate 20000 1000

ntp clock-period 17178446

ntp server 66.27.60.10

end

SWITCH:

!

version 12.1

no service pad

service timestamps debug uptime

service timestamps log uptime

service password-encryption

!

hostname SWITCH2950-12

!

username Admin privilege 15 secret 5 $1$qMty$HAjO6PjGEwDDl2FYHqnSY.

clock timezone gmt+1 1

clock summer-time gmt+2 recurring last Sun Mar 2:00 last Sun Oct 3:00

ip subnet-zero

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

!

interface FastEthernet0/1

switchport access vlan 10

switchport mode access

!

interface FastEthernet0/2

switchport access vlan 20

switchport mode access

!

interface FastEthernet0/3

switchport access vlan 30

switchport mode access

!

interface FastEthernet0/4

!

interface FastEthernet0/5

!

interface FastEthernet0/6

!

interface FastEthernet0/7

!

interface FastEthernet0/8

!

interface FastEthernet0/9

!

interface FastEthernet0/10

!

interface FastEthernet0/11

!

interface FastEthernet0/12

switchport mode trunk

!

interface Vlan1

ip address 192.168.1.251 255.255.255.0

no ip route-cache

!

ip default-gateway 192.168.1.254

ip http server

!

line con 0

password 7 130105040606167C7D04

login

speed 115200

line vty 0 4

privilege level 15

password 7 050F14192C465C5F4F25

login local

transport input telnet

line vty 5 15

privilege level 15

password 7 050F14192C465C5F4F25

login local

transport input telnet

!

ntp clock-period 17178532

ntp server 66.27.60.10

!

end

Didier1966 · ‎11-29-2010

I JUST FOUND THE PROBLEM :

THE DEFAULT GATEWAY IN THE SWITCH WAS WRONG !!!

IT HAS TO BE :

192.168.1.250 AND NOT 192.168.1.254

Best Regards,

Didier

Richard Burts · ‎11-30-2010

Didier

I am glad that you got it working - and that you found the solution yourself. Thank you for posting back to the forum to inform us that you had solved it and what the problem was. It makes the forum more useful when people can read about a situtation and can read what the problem was and how it was solved. You have contributed to this and provided a reminder that sometimes it is simple things like is the gateway address correct that is the root of the problem.

HTH

Rick

HTH

Rick

Didier1966 · ‎11-30-2010

Hello Rick,

I think that it is completely normal to post a reply when the case is solve , your time is really too expensive to spend it with a case that is already solved.

During this time you can maybe help someone that has a bigger problem.

In this forum , I miss the button solved , or maybe I do not know where it is

Best Regards,

Didier

Richard Burts · ‎11-30-2010

Didier

I wish that it were completely normal to post to the forum when you find a solution to a problem. But my experience is that not everyone does this. And I agree with you that this results in time being wasted.

There is confusion about the button that I refer to as solved. Perhaps now it says answered or something like that. But in my post there is a green check mark on a yellow background which is the indication that the response answered (or solved) the issue. The original poster is the only one who can give that mark, and it looks like you did. The check mark shows up in the listing of the discussions (when you have logged in to the forum) and is the indicator to other readers that the issue is answered (or solved).

HTH

Rick

HTH

Rick