Cisco 851 access

Posted on 2011-09-06
Last Modified: 2012-05-12
I have a Cisco 851 that I am trying to access.  DHCP works, and I am able to obtain an ip.  I think the router is at factory default settings.  When I try to telnet or ssh the connection is refused (I assume Cisco's default config).  The documentation I see for this router makes reference to "sdm".  But I cannot seem to find the download available anywhere.  Can someone point me in the right direction, or provide instructions for accessing via aux port.

Question by:ycgtech
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Accepted Solution

SuperTaco earned 500 total points
ID: 36492904
do you have a console cable?  if so, and you don't have a serial port just ;ick up a serial converter.  to enable telnet access you need to have the enable password 9if it's out of the box it should be cisco, if not factory reset the 851 (read; creds are cisco | cisco)

the string you'll need is

conf t
line vty 0 4
password PaSsWoRd

(this is the bascis)

SDM is the "Secure device manager" and it's not really available for download anymore, it's been replaced by the CCP (Cisco Configuration Professional)  If you have an account on Cisco's site, you can download it.  

You can also try to get into the IP of that 851, that should get you to the web interface (sometime it's enabled by default)
LVL 17

Expert Comment

ID: 36493696
By default telnet & SSH are disabled on cisco devices. As mentioned above you will need a console cable to connect to the device to be able to configure this.

To enable telnet do the following in the CLI (This is assuming the device already has a reachable IP configured on it):

conf t

username NAME privilege 15 secret PASSWORD

line vty 0 4
transport input telnet
login local

SSH is the more secure protocol and I suggest using this if you are managing this router for a business

To enable SSH do the following:

conf t

username NAM privilege 15 secret PASSWORD
ip domain-name DOMAIN.COM
crypto key generate rsa
How many bits in the modulus [512]: 1024 (I suggest using 1024 bit encryption but the default will work also)

line vty 0 4
login local
transport input ssh

LVL 17

Expert Comment

ID: 36493706
also you can check to see if SDM is installed by default on your router by issuing the show flash command in the CLI. the file you are looking for will be called something like sdm.tar

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