04-27-2013 09:06 AM - edited 03-07-2019 01:04 PM
I have searched on here but can't find the exact answer i am looking for. I have a cisco 1760 router and a 2950 switch. The router has an ethernet wic card added so i have two ethernet connections available. I would like to connect the cable modem gatway to the router through one of the ethernet connections on the router and then to the switch. I cannot seem to get this setup to work. There are several different ways i have seen posted to accomlish this. dhcp, no dhcp, creating a seperate network, and giving the e0/0 an ip address within the range of the cable gateways network addresses. None of this has worked. Can anybody post the commands that need to be entered on the router to make this possible?
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04-27-2013 09:20 AM
Hello, I am assuming that your ISP is giving out addresses via DHCP....
And I will also assume that we want to set up our router to give out DHCP in our LAN to our PC's and Laptops etc...
So what we need to do is this:
conf t
!
interface e0/0
description ## INTERNET ##
ip access-group MY_WAN in
ip address dhcp
ip nat outside
no shut
!
interface e0/1
description ## MY LAN ##
ip address 192.168.1.1 255.255.255.0
ip nat inside
!
ip access-list standard MY_LAN
permit 192.168.1.0 0.0.0.255
!
ip access-list extended MY_WAN
permit tcp any any established
deny tcp any any
permit ip any any
!
ip nat inside source list MY_LAN interface e0/0 overload
!
ip dhcp excluded-address 192.168.1.0 192.168.1.99
!
ip dhcp pool MY_LAN
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 8.8.4.4 8.8.8.8
In this config I have applied an ACL just for some protection to my router and my internal network to allow only established connections that Ive made from my LAN to come back to me. Anyone trying to initiate a connection to your router will be denied. Everything else is permitted. But you can change this to be more specific rather than broad.
On your switch, if you leave all ports in vlan 1 and have them as access ports, this should work.
Hope this helps
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 09:20 AM
Hello, I am assuming that your ISP is giving out addresses via DHCP....
And I will also assume that we want to set up our router to give out DHCP in our LAN to our PC's and Laptops etc...
So what we need to do is this:
conf t
!
interface e0/0
description ## INTERNET ##
ip access-group MY_WAN in
ip address dhcp
ip nat outside
no shut
!
interface e0/1
description ## MY LAN ##
ip address 192.168.1.1 255.255.255.0
ip nat inside
!
ip access-list standard MY_LAN
permit 192.168.1.0 0.0.0.255
!
ip access-list extended MY_WAN
permit tcp any any established
deny tcp any any
permit ip any any
!
ip nat inside source list MY_LAN interface e0/0 overload
!
ip dhcp excluded-address 192.168.1.0 192.168.1.99
!
ip dhcp pool MY_LAN
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 8.8.4.4 8.8.8.8
In this config I have applied an ACL just for some protection to my router and my internal network to allow only established connections that Ive made from my LAN to come back to me. Anyone trying to initiate a connection to your router will be denied. Everything else is permitted. But you can change this to be more specific rather than broad.
On your switch, if you leave all ports in vlan 1 and have them as access ports, this should work.
Hope this helps
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 10:18 AM
ok i entered all the commands but it did not work. I have never configured a switch before so i am not sure what to do there. also will this be static or dynamic ip addresses?
04-27-2013 10:27 AM
Could you be a bit more elaborate please? What didn't work?
Could you kindly post your config and erase any passwords or sensitive information. This way I will be able to assist further.
Thank you
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 10:38 AM
Sorry, should have been more specific.
Current configuration : 1129 bytes%PQUICC_ETHER-1-LOSTCARR: Unit 0,
!s
! Last configuration change at 02:29:35 UTC Sun Mar 3 2002 Interface FastEtherne
problem?
pro
!e
version 12.38:24.711: %L
service timestamps debug datetime msecerface FastEtherneransceiver
service timestamps log datetime msecs now available
M
t0/0, change
no service password-encryption7.024:
Mar 3 00:48:24.807: %
!N
hostname Routerrface Ethernet0
!,
!h
no aaa new-modeled from console
ip subnet-zerochanged state
!
!w
ip dhcp excluded-address 192.168.1.0 192.168.1.99%LINK-3-UPDOWN: Interface Seria-UPDOWN: L
!
ip dhcp pool MY
changed state to downm
description ## MY LAN ##3 00:48:25.836: %LINEPROT
ip address 192.168.1.1 255.255.255.0 Serial1/1,ip min/avg/max = 1/1/4 ms:
ip nat insideEthernet0/0, c
shutdownte t
p
speed autod state to
!w
interface Serial1/0ET
Mar 3 00:48:29.
no ip address-5-UPDOWN: Lin
shutdown on Inter
!c
interface Serial1/1rne509: %LINK-5-CHA
no ip address Serial
probl
shutdowne
Mar 2
!2
ip access-list standard MY_LAN
--More--
Mar 3 02:54:00.897: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver
permit 192.168.1.0 0.0.0.255
!
ip access-list extended MY_WAN
permit tcp any any established
deny tcp any any
permit ip any any
!
!
line con 0
line aux 0
line vty 0 4
!
no scheduler allocate
!
end
04-27-2013 10:47 AM
Bernard
Thanks for trying to post the config. Unfortunately it seems to be incomplete and quite mixed in its order.
I would also suggest that we wait to talk about the switch until we get the router working. After the router is working it may be quite simple to get the switch working.
So please give us a better output of the running config. And also give us a more specific explanation of what does or what does not work on the router. (most especially does the router get connected to the provider cable modem? does the router get assigned an IP address? is the router learning a default route from the provider cable mode.?)
HTH
Rick
04-27-2013 11:08 AM
sorry should have been more specific to begin with. the router does not get an ip address assigned to it. The computers Lan connection says it can see the network but cannot reach the dns server.
04-27-2013 11:35 AM
Hello Bernard,
from your PC - are you able to ping 192.168.1.1 ?
What do you see when you open cmd and do 'ipconfig'
Do you have an IP address beginning with 192.168....
Just want to make sure the LAN is working properly. Then we can look at why the internet link does not work and why you do not get an IP address.
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 11:59 AM
i can successfully ping 192.168.1.1 from the pc. my majic jack phone works fine but the computer cannot connect to the Internet. when i click diagnose on the lan sometimes it says ip not configured properly or dns server not reachable and sometimes it says both of them.
04-27-2013 10:48 AM
Wow :-) I can't fully make out what the config is like - your console session must be quite annoying with those messages!
Could you kindly do this please:
router# term len 0
router# show run
and then paste the config again. Thank you.
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 10:52 AM
Also, the switch should have a default config similar to this...
Switch#show run
Building configuration...
Current configuration : 971 bytes
!
version 12.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
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
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface Vlan1
no ip address
shutdown
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
end
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 10:59 AM
Here is the config after entering those commands. not sure if i have a bad router or what. it is very difficult to enter commands because they keep getting interrupted by the error messages
Building configuration...a0/0ocating add
problem?
Current configuration : 1129 bytes 3 01:52:52.956: %PQUICC_ETHER-1-L
!T
! Last configuration change at 02:29:35 UTC Sun Mar 3 200221 bytes of non-volatile configuration
problem?
!
version 12.3135:
R1(con
service timestamps debug datetime msec.
R1(config-if)#description ##MY LAN##
service timestamps log datetime msecR1(config-if)#ip address 192.168.1.1
no service password-encryptionETHER-1-LOSTCARR: Unit 0, lost
!a
hostname Router.958: %PQUICC_E
!E
!1
no aaa new-model, lost carrier.
ip subnet-zeromputer Softwa
!r
!l
ip dhcp excluded-address 192.168.1.0 192.168.1.99LOSTCA
problem?s clause
R1(config-if)#ip nat
!
interface Ethernet0/0
description ##internet##R1(config-std-nacl)#23:21
ip address dhcpar 3 01:55:52.9
ip access-group MY_WAN inR: Unit 0, lost carrier. T
ip nat outsidel1/0, change
IO
half-duplexSoftware (C1
!0
interface FastEthernet0/0 2 2
problem?9: %PQUIC
description ## MY LAN ##CC_ETHER-1-LOSTCARR: Unit
ip address 192.168.1.1 255.255.255.0chnical Support: http://www.cisco.com
ip nat inside?
Mar
shutdownblem?1: %
speed auto 01:57:52.9
!:
interface Serial1/0TCARR: Unit 0, lost
no ip addressceiver
shutdown
ip classless
!
no ip http server
!
ip access-list standard MY_LAN
permit 192.168.1.0 0.0.0.255
!
ip access-list extended MY_WAN
permit tcp any any established
deny tcp any any
permit ip any any
!
!
line con 0
line aux 0
line vty 0 4
!
no scheduler allocate
!
end
04-27-2013 11:02 AM
Oh, okay try this please.. (Assuming you are using console)
conf t
!
no logging console
!
end
This should stop the messages for now.
Please rate useful posts and remember to mark any solved questions as answered. Thank you.
04-27-2013 12:02 PM
this one helped a lot. no more error messages while i am trying to enter commands
04-27-2013 12:06 PM
Okay great! Making progress.
So we know our LAN is OK...
Do you mind showing us the configuration on the router again please? Just want to make sure it's not the configuration.
Thank you
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