[Guide] How to perform a Cisco router password recovery without losing your configuration

Forgot your Cisco router password?  Did you know you can change them without losing your configuration?  In this brief how-to, I will walk you through it. In order to perform a password recovery, you will need to reboot the router a couple of times.  This means downtime, but it is a good sacrifice to make in order to get your passwords reset.

First, hook up the DB9 end of the standard light blue serial cable to your serial port.  The other end of the cable should plug into the port labeled “Console” on the back of the Cisco router.  If you do  not have a serial port, then you'll need to go purchase a USB-to-serial adapter cable and install it on your computer.

Now that your hardware is connected, establish a serial connection with the router.

The settings you need are:
Baud: 9600
Data bits: 8
Parity: No
Stop bits: 1
Flow Control: None

On Windows, I use putty for this connection.  Yes, putty can be used to make serial connections as well as telnet/ssh.  Hyperterminal works great as well.  On Linux, I use minicom and on FreeBSD/OpenBSD, I use cu (cu -s 9600 -l /dev/cuad0).

Reboot the router and press the Break key to interrupt the boot sequence.

For break key sequences, refer to this Cisco link: http://www.cisco.com/c/en/us/support/docs/routers/10000-series-routers/12818-61.html

Type confreg 0x2142.  This tells the router to bypass NVRAM during bootup.  In other words, your existing configuration won't be loaded.  The good news is that it won't be deleted either.

Type reset to reboot the router.  Answer No when prompted to run setup.

Type copy start run.  This loads your startup configuration into memory.
Now, if you type a show run config, you'll see the router configuration.  Also, you should notice that your router name is now in the prompt instead of the default “Router”.

To Change the enable secret - “enable secret new_password”
To Change the admin log in - “username admin_name password new_password”

Change the register back to 0x2102:
config-register 0x2102

When the router reboots it will load the old configuration with the new password.

Save the password so that it will be persistent during reboots, type copy run start

Reboot the router by typing reload at the enable prompt.

Now, keep that password in a nice safe place – in your head does not count.  I keep mine saved in a safe place for future retrieval and I make sure my customers have a copy as well.  Remember, passwords are nice until you forget them.

To know more: How to reset a Cisco Router
Repost from: Password Recovery from a Cisco Router

Get paid to share your links!

Megapop configuration over ATM (Consumer router - ADSL connection)

Login the router and access to Channel Config

Make sure there is no record under Current ATM VC table.

Add new Channel Configuration 
Default Route selection: Auto
VPI: 8
VCI: 35
Channel Mode: IPoA
Encapsulation: LLC
NAPT: Disable
802.1q: Disable
Local IP address: Customer WAN IP
Remote IP Address: Singtel WAN IP
Netmask: 255.255.255.252

Check and make sure the ATM VC has been setup properly.

Setup LAN Interface

Enable LAN DHCP

Add routing - Advance -> Routing -> Static Routes

Make sure the static route is enable

Lastly, go to maintenance, Save and reboot

Get paid to share your links!

[HOW] setup port forwarding in Thomson Router TG585 v7 / v8

Step 1
Open your favorite web browser and input your routers ip address in the address bar.
Please note that you must have the http:// in order to connect to your router/modem properly.

Step 2
Once logged into your router click on the "Toolbox" tab on the left.
Under "Toolbox" click "Game & Application Sharing".
Once the page is done loading click on "Create a new game or application".

Step 3
For Name, give the new rule a name.
Choose "Manual Entry of Port Maps and then click "Next".

Step 4
For 'Protocol' Choose 'TCP' or 'UDP' depending on which you need to use.
For 'Port Range' enter the ports to be forwarded.
Example: 2100 to 2200 or 3000 to 3000
Click 'Add'.
Repeat this step for all ports.
Once you have entered all the ports for this entry click 'Assign a game or application to a local network device'.

Step 5
In the "Game or Application" list, choose the name of the new rule you created.
For "Device" you can either choose the computer name to forward to, or choose "User-Defined" to manually enter a IP address.
If you choose "User-Defined" a new text box will show up, enter the local IP to forward to here.
Once you are all done click 'Add'

All done.


Reference:

http://portforward.com/english/routers/port_forwarding/Thomson-Alcatel/SpeedTouch585/Utorrent.htm

http://www.pcwintech.com/port-forwarding-thomson-tg585-v7-thomson-firmware

[Cisco] Setup ADSL connection

Here is the example for ADSL setup:
no service pad service timestamps debug datetime localtime service timestamps log datetime localtime service password-encryption ! hostname ******TYPE YOUR HOSTNAME HERE****** ! enable secret *******************TYPE YOUR SECRET PASSWORD******************* username <username> password <password> no aaa new-model ip subnet-zero no ip source-route no ip domain lookup ! ! ip dhcp excluded-address <192.168.0.1> <192.168.0.29> ip dhcp excluded-address <192.168.0.241> <192.168.0.255> ! ip dhcp pool dhcppool import all network <192.168.0.0> <255.255.255.0> dns-server **** TYPE DNS SERVER IP ADDRESS (Follow by spacebar)**** default-router <192.168.0.1> ! no ftp-server write-enable ! interface vlan1 description <description> ip address <192.168.0.1> <255.255.255.0> no ip redirects no ip unreachables no ip proxy-arp ip nat inside ip virtual-reassembly ip tcp adjust-mss 1350 no ip mroute-cache ! interface ATM0 no ip address no atm ilmi-keepalive pvc 0/38 encapsulation aal5mux ppp dialer dialer pool-member 1 ! dsl operating-mode auto ! interface Dialer0 description <description> ip address negotiated ip mtu 1492 no ip redirects no ip unreachables no ip proxy-arp ip nat outside ip virtual-reassembly encapsulation ppp no ip route-cache no ip mroute-cache dialer pool 1 dialer-group 1 ppp authentication chap callin ppp chap hostname ***** adsl username ***** ppp chap password ***** adsl password ***** ! ip nat inside source list 100 interface Dialer0 overload ip local pool dhcppool 192.168.0.101 192.168.0.105 ip route 0.0.0.0 0.0.0.0 Dialer0 no ip http server no ip http secure-server ! dialer-list 1 protocol ip permit access-list 1 permit <external ip address to access telnet from> <mask> access-list 100 permit ip <192.168.0.0> <0.0.0.255> any ! ********** SAMPLE PORT FORWARDING ********** ip nat inside source static tcp 192.168.0.31 3389 interface Dialer0 3389 ip nat inside source static udp 192.168.0.100 8503 interface Dialer0 8503 ! ! line con 0 password *****TYPE YOUR CONSOLE PASSWORD***** login no modem enable stopbits 1 transport output all line aux 0 stopbits 1 transport output all line vty 0 4 access-class 1 in exec-timeout 0 0 password *****TYPE YOUR TELNET PASSWORD***** login transport input all transport output all ! scheduler max-task-time 5000 ! end



Refenrence:
http://www.cisco.com/en/US/docs/routers/access/800/850/software/configuration/guide/pppoanat.html
http://www.certforums.com/forums/routing-switching/19952-cisco-877w-adsl-setup.html
http://exewiki.exetel.com.au/index.php?title=Cisco_-_Sample_Config_for_Cisco_877

How to reset a Cisco Router

What you will do when you face a login problem once you get a Cisco Router?
Will there any reset button on Cisco Router?

Definitely is NOT!

By the way, here is the step guide you on resetting Cisco Router to factory default setting.
Stay Calm =)

To reset a Cisco router to factory default (removing the startup configuration file), you need to be perform these steps:

To erase the configuration file, issue the erase nvram: command.
Reload the router and attempt to break into ROM Monitor (ROMmon) by issuing the break sequence (usually Ctrl and break from the Hyperterminal) from a console connection.

You should see this ROMmon prompt:
rommon 1>

Then, Change the configure register value to ignore the startup configuration by issuing the confreg command, as shown in this example:
rommon 2> confreg 0×2142

To reload the router, issue the reset command, as shown in this example:
rommon 3> reset

After the router boots, issue the enable command at the Router > prompt.
Router > en
The prompt changes to Router#, indicating that the router is now in privileged mode.

To enter config mode, issue the config terminal command.
You should now see a prompt as below.
Router(config)#

To change the configure register to recognize the startup configuration, issue the config-register command, as shown in this example:
Router (config)# config-register 0×2102

To break out of configuration mode, press Ctrl and Z.
To save the blank configuration, issue the copy-running config-startup config command.

Good Luck =)


Reference: http://www.cisco.com/en/US/products/sw/iosswrel/ps5187/products_tech_note09186a00802017a1.shtml

DHCP configuration on Cisco Router or switch

Let's begin to configure basic DHCP on IOS-based router.
May configure through console cable or Ethernet cable, however please plug into correct port and use correct method access into IOS command line console.

To configure Cisco IOS DHCP, follow these steps, which include sample commands:

1. Configure an IP address on the router's Ethernet port, and bring up the interface. (On an existing router, you would have already done this.)
   
Router(config)# interface ethernet0/0 Router(config-if)# ip address 1.1.1.1 255.0.0.0 Router(config-if)# no shutdown
2. Create a DHCP IP address pool for the IP addresses you want to use.
Router(config)# ip dhcp pool mypool
3. Specify the network and subnet for the addresses you want to use from the pool.
Router(dhcp-config)# network 1.1.1.0 255.0.0.0
4. Specify the DNS domain name for the clients.
Router(dhcp-config)#domain-name mydomain.com
5. Specify the primary and secondary DNS servers.
Router(dhcp-config)#dns-server 1.1.1.10 1.1.1.11
6. Specify the default router (i.e., default gateway).
Router(dhcp-config)#default-router 1.1.1.1
7. Specify the lease duration for the addresses you're using from the pool. (i.e: 7days and 12hours / half day)
Router(dhcp-config)#lease 7 Router(dhcp-config)#lease 0 12
8. Exit Pool Configuration Mode.
Router(dhcp-config)#exit

Next, exclude any addresses in the pool range that you don't want to hand out.
For example, let's say that you've decided that all IP addresses up to .100 will be for static IP devices such as servers and printers. All IP addresses above .100 will be available in the pool for DHCP clients.

Here's an example of how to exclude IP addresses .100 and below:
Router(config)#ip dhcp excluded-address 1.1.1.0 1.1.1.100

Then, enter the ipconfig /renew command on the laptop to receive an IP address. After you have the IP address, enter the ipconfig /all command.

This is the sample output:

May also refer to http://www.trainsignal.com/blog/cisco-dhcp if you are looking for DHCP relay or setup router as DHCP client

Reference:
http://www.techrepublic.com/article/configure-dhcp-on-a-cisco-router-or-switch/5690240
http://www.trainsignal.com/blog/cisco-dhcp

[HOW] Migration from DSL to Elite

Senario 1: Setup ELITE connection
Senario 2: Migration from DSL to Elite


Don't worry, and just follow the guide on Senario 1,
WAN IP address most probably is different from DSL, so you may just ignore the WAN IP from DSL,
but it has LAN IP address for their network, please check clearly for what LAN they are using,
and It maybe same with what Singtel gave to you.

Besides that, please check on their current router, is there any NAT translation setup or port forwarding.
If there is, please configure on this new connection router also.

NOTE: Please use back the LAN IP that they are currently using and do test the network.

To change admin password or create more user account to access,

Please check System time and correct it too,

One last time, MOST important,

Please remember to SAVE it after you finish all your configuration,

Otherwise, after you turn off the power, everything will be gone… 

Good Luck for everyone.

[HOW] Setup Elite connection (Singtel, Starhub, M1)

Let's start to access HP MSR-a900. Power up and connect correct cable into the device's LAN port.
Open browser and type http://192.168.1.1/

NOTE: this is the default IP address.

Then web user login page will appear and need to enter username and password to login.
Username: admin
Password: admin

NOTE: don't forget to enter the verification code.

After login successfully, will saw a page as below.
For ADSL configuration, may just go ahead to select on wizard and select basic configuration.

However, this page is guide to configure ELITE connection.
Firstly, have to select WAN Interface Setup under the Interface Setup.

Here is an example:
Singnet given ELITE information as below:-
WAN IP:
10.185.60.109 (Singtel)
10.185.60.110 (Customer)
Subnet Mask: 255.255.255.252

LAN IP:
10.73.203.80 - 10.73.203.95
Subnet Mask: 255.255.255.240

DNS server:
165.21.83.88
165.21.100.88

So after the first step, this is what will display in WAN Interface Setup

Then , please select either Ethernet0/0 or Ethernet0/1 as WAN port, click on the modify icon.

For ADSL, will just select PPP0E as connection mode.
Now, Manual will be the connection mode for this setup.

Next, enter the WAN port information that given by Singnet. Refer to snapshot.

Please take note in:
IP address - WAN IP (Customer)
IP Mask - WAN IP subnet mask
Gateway address - WAN IP (Singtel)
DNS1 and DNS2 - Singtel DNS

Just hit on Apply button after complete filling all the information and there is a window pop out shown that configuration is modifying the router.

After that, the IP address will shown on the WAN Interface table.

Now, we proceed to LAN interface setup by choose LAN Interface Setup in Left panel.

By default, all the 4 LAN ports are in same VLAN1, and we are not going to change anything in VLAN, unless you have 2 network.
So just continue to select VLAN interface setup.

As singtel is given a pool of IP address, so we just choose one from it,
BUT, please don’t take the 1st IP address and Last IP address in the pool as they are network address and broadcast address.
So we select 2nd IP address,

Then click apply, you may lost connection after apply it as you are using LAN port to configure it.
Unless you are using Console cable =)

The DHCP server, we can just ignore if the user didn’t require for it and they may have DHCP server in their network.

Finally, we are done here.

However, we still need to remember the important setting,
NAT, network address translation,
We knows, Singtel is given us Public IP address, but our customer network is using Private IP address,
So we do need NAT to help the network work well.

First, we need to check whether their network has firewall and NAT is managed by other devices,
If no, please do configure NAT in this router as well.
If Yes, we need to disable the NAT in this router!

NAT configuration is at left panel

Please delete whatever you see in the right bottom panel and make sure the network is working well.

Lastly, REMEMBER to save the configuration after complete everything.