My Netwok Dictionary

For those who often work on remote Cisco device is very useful to have the opportunity to recover the previous configuration changes made (perhaps because it has lost connectivity …).

To do this it is possible to set an automatic reload, which will allow us to restart the router with its original configuration (startup-config) and recover the connection.

The command is as follows:

Router # reload in?
Delay before reload (mmm or hhh: mm)
Router # reload in 45
Router # reload in 45?
LINE Reason for reload

Router # reload in 45 For Test?
LINE
Router # reload in 45 For Test
System Configuration Has Been Modified. Save? [Yes / no]: n
Reload scheduled for 12:18:08 MET +1 Thu Aug 3 2006 (45 minutes) by foo on vty0 (10.55.198.121)
Reload reason: For Test
Proceed with reload? [Confirm] Read the rest of this entry »

The advice to avoid some of the most common mistakes that can create serious problems.

1. Redistribution of filtering
In the redistribution of routing, you need to filter properly routers. That is absolutely not to apply filters is usually a practice that creates problems for some relief, but managing a complex network filters and sketched in summary fashion is a serious difficulty for an administrator It. The best way to avoid this, obviously is to not make the redistribution. Read the rest of this entry »

These devices are essential elements of any wired or wireless network. It is therefore essential to understand how to manage the traffic and how to set paths to follow.

As the Router enter in the OSI model
Although only a theoretical framework, the OSI model is a good way to see how all these protocols, addresses and network devices (such as just the router) complement one another.
The Layer 2 and 3 of the OSI model are those that apply in this case. The Layer 2 Data Link layer is where there exist the Ethernet protocol, the MAC addresses and switches. Layer 3, network layer, is where there exist the IP protocol, IP addresses and routers. Consider that all traffic is sent from your computer, starting from Layer 7 (application of your network) up to Layer 1 (physical layer). Through the physical layer, medium traffic flows on your network (whether wired or wireless to a network).

The traffic passes through a router only if it is not on your local LAN. Routers operate at Layer 3 but above all must interpret at least 1 to 3 layers. Many parsed routers each type of traffic up to layer 4 to 7 and in various ways, but to simplify the concept we consider that only operate at Layer 3. Read the rest of this entry »

Many network administrators would have perhaps never been aware of the fact that their router may be subject to an attack. In fact, the router operating systems are as vulnerable as the network operating systems. Read the rest of this entry »

Installing the Cisco Unified CME Router

First make sure you have installed your router an IOS suitable for CME.
The CME software includes a set of files, divided into the following categories.

Basic files: These are the core files that are required to operate the CME. These files also include firmware that allows Cisco IP phones to operate.
Gui files: These files make it possible to control the CME web.
XML template files: These files determine the control structure of Web pages for the configuration of the CME.

Changing these files allow you to create different levels of administration.

• MOH files: audio files are used for Music on Hold (MOH)
• Script files: Defined as Various Tool Command Language (Tcl) script files to provide advanced functions in the CME (eg automatic call distributor ACD)
• Miscellaneous files: There are additional files that allow you to customize the ring tones or background different models Cisco IP Phones

Read the rest of this entry »

L2L connections

Land to land (site to site) connections are best suited for routers since it can do multiple dynamic site VNP

• WAN extension of a classical design
• Configurations Steps
• Handle design and Policy
• Verify connectivity without IPSec (ping)
• Create extended ACL to allow IPSec traffic into the router
• Configure ISAKMP / IKE Phase 1 Policies
• Create extended ACL That Defines Which is traffic to be protected for the tunnel
• Create transform sets
• Create a crypto map That binds together the peer’s information protection
• Activate on the crypto map interface
• Test IPSec tunnel

Read the rest of this entry »

The process of maintaining the routing information may generate errors if there is no quick and accurate convergence between the routers. In design of complex networks may occur routing loops or loops. Routers transmit constant updates to their neighbors, if a router B receives an update of a network that has fallen, this forward this information to all its neighbors including the router B who first informed him of novelty, turn the router B will report that the network has fallen into router to form an endless loop. Read the rest of this entry »

The router gives us the possibility of aid because it is difficult to memorize all available commands, the question mark (?), And the Keyboard tab give us the necessary assistance to that effect. The full tab not remembers the commands complete or do not want to write in full.

The? Placed immediately after a command that shows all start with those letters, placed after a space (spacebar +?) We list all the commands that can run in that position. Read the rest of this entry »

When you first start a Cisco router, there is some initial configuration. The router software will ask for a minimum set of details through a dialogue called optional setup. Startup routines Cisco IOS software are designed to initialize the router operations.

For this, the start-up routines should do the following:

• Make sure the router has verified hardware (POST).

• Locate and load the Cisco IOS software that uses the router for your operating system.

• Locate and apply the setup instructions for the specific attributes of the router, the protocol functions and interface addresses. Read the rest of this entry »

For the initial configuration of the router using the console port connected to a console or rollover cable and RJ-45 to DB-9 COM1 port to connect to the computer. This must have terminal emulation software such as HyperTerminal.

The configuration parameters are:
• The appropriate COM port
• 9600 baud
* 8 data bits
• No parity
• 1 stop bit
• No flow control Read the rest of this entry »