[taken from IE VOL1 workbook]
It’s best to only allow SSH access on your VTY ports. Here’s how you can do it:
1) Configure a domain name on your router:
Rack1R4(config)#ip domain-name internetworkexpert.com
2) Generate the keys:
Rack1R4(config)#crypto key generate rsa general-keys modulus 512
3) Configure the VTY ports with SSH access only:
Rack1R4(config)#line vty 0 4
Rack1R4(config-line)#transport input ssh
4) enable local login [...]
Archive for the ‘tutorials’ Category
How to configure SSH on your router
Posted in tutorials, tagged cisco routers, configuring ssh, ssh on August 13, 2008 | 2 Comments »
Going back to the “intermediate” router with term server
Posted in tutorials, tagged switching between routers, term server on August 13, 2008 | Leave a Comment »
[hint taken from Brian Dennis's CoD]
Suppose you are using a term server to login to all your routers. And you’re on R1. You SSH to R4. How do you go back to R1? See below:
ccie-ts#1
[Resuming connection 1 to r1 ... ]
Rack1R1#ssh -l CISCO 155.1.146.4
Password:
Rack1R4>
<—-now you want to go back to R1, how would you do [...]
routing to next-hop vs routing to interface
Posted in InternetworkExp, tutorials, tagged arp, multipoint broadcast interface, proxy arp, routing, static routes on August 7, 2008 | Leave a Comment »
concept learnt from IE’s Vol5.0 workbook for “IP Routing”
When routing to a next-hop value the router performs L2 to L3 resolution on the next-hop address. (e.g. ip route 150.1.4.4 255.255.255.255 155.1.146.4). So in the arp table, you’ll see the MAC for ip address: 155.1.146.4.
When routing to an INTERFACE, the router performs L2 to L3 resolution [...]
Solving your subnetting problems
Posted in tutorials, tagged cidr, ip, subnetting, vlsm on June 7, 2008 | 1 Comment »
(source: CCBOOTCAMP study guide)
Problem: Find subnet mask for a network in which you need no more than 60 hosts
Using the table below:
We see that the subnet we need is with 2 bits, so it should be: 255.255.255.192, Number of subnets 4, and number of Hosts are 62.
Bits
1
2
3
4
5
6
7
8
Binary
128
64
32
16
8
4
2
1
Subnets
128
192
224
240
248
252
254
255
#Hosts (Binary – 2)
126
62
30
14
6
2
0
0
# of [...]
Prefix-List tutorial
Posted in tutorials, tagged prefix-list on June 7, 2008 | 1 Comment »
This is such an awesome tutorial:
http://ccienotes.blogspot.com/2007/08/ip-prefix-list.html
I was having a bit of trouble understanding them….now it’s pretty clear
