Thursday, December 13, 2018

Frame tagging

To Identify the VLAN to which a packet belongs and change tagging to assign a numeric value to each frame in a multi-VLAN network. This ensures that the switches know which ports to send.

Think of the following network topology.



The top list contains two VLANs, namely VLAN 3 and VLAN 4. Host A sends a shipping packet to SW1. Switch SW1 receives the packet, identifies the packet with VLAN ID 3, and sends it to SW2. SW2 receives the packet, searches for VLAN ID, and passes only the Fa0 / 1 packet because only this port is in VLAN 3. Host B and Host C do not receive the packet because they are in a VLAN other than Host A.

Sunday, December 9, 2018

Static Routing Configuration using Serial Port using Cisco Packet Tracer


 Example :





Static routing Configuration on ROUTER 0:



R(config)#ip route 1.0.0.0 255.0.0.0 2.0.0.2


R(config)#ip route 9.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 8.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 5.0.0.0 255.0.0.0 6.0.0.2


R(config)#ip route 3.0.0.0 255.0.0.0 4.0.0.2

 


Static routing configuration on ROUTE 1:



R(config)#ip route 9.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 7.0.0.0 255.0.0.0 4.0.0.1


R(config)#ip route 8.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 7.0.0.0 255.0.0.0 4.0.0.1


R(config)#ip route 1.0.0.0 255.0.0.0 2.0.0.2


R(config)#ip route 2.0.0.0 255.0.0.0 4.0.0.1


R(config)#ip route 5.0.0.0 255.0.0.0 6.0.0.2


R(config)#ip route 6.0.0.0 255.0.0.0 4.0.0.1



Static Routing configuration on R2:



R(config)#ip route 9.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 7.0.0.0 255.0.0.0 2.0.0.1


R(config)#ip route 8.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 7.0.0.0 255.0.0.0 2.0.0.1


R(config)#ip route 5.0.0.0 255.0.0.0 6.0.0.2


R(config)#ip route 6.0.0.0 255.0.0.0 2.0.0.1


R(config)#ip route 3.0.0.0 255.0.0.0 4.0.0.2


R(config)#ip route 4.0.0.0 255.0.0.0 2.0.0.1


 


Static routing configuration on R3:



R(config)#ip route 1.0.0.0 255.0.0.0 2.0.0.2


R(config)#ip route 2.0.0.0 255.0.0.0 6.0.0.1


R(config)#ip route 3.0.0.0 255.0.0.0 4.0.0.2


R(config)#ip route 4.0.0.0 255.0.0.0 6.0.0.1


R(config)#ip route 8.0.0.0 255.0.0.0 6.0.0.2


R(config)#ip route 8.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip routr 7.0.0.0 255.0.0.0 6.0.0.1


R(config)#ip route 7.0.0.0 255.0.0.0 6.0.0.1


R(config)#ip route 9.0.0.0 255.0.0.0 7.0.0.2


R(config)#ip route 7.0.0.0 255.0.0.0 6.0.0.1



Static routing configuration on R4:



R(config)#ip route 1.0.0.0 255.0.0.0 2.0.0.2


R(config)#ip route 2.0.0.0 255.0.0.0 7.0.0.1


R(config)#ip route 5.0.0.0 255.0.0.0 6.0.0.2


R(config)#ip route 6.0.0.0 255.0.0.0 7.0.0.1


R(config)#ip route 3.0.0.0 255.0.0.0 4.0.0.2


R(config)#ip route 4.0.0.0 255.0.0.0 7.0.0.1




Now check routing table on Middle router:



#show ip route



Gateway of last resort is not set



S 1.0.0.0/8 [1/0] via 2.0.0.2



C 2.0.0.0/8 is directly connected, Serial0/1/1


S 3.0.0.0/8 [1/0] via 4.0.0.2


C 4.0.0.0/8 is directly connected, Serial0/0/1


S 5.0.0.0/8 [1/0] via 6.0.0.2


C 6.0.0.0/8 is directly connected, Serial0/0/0


C 7.0.0.0/8 is directly connected, Serial0/1/0



S 8.0.0.0/8 [1/0] via 2.0.0.2 [1/0] via 7.0.0.2



S 9.0.0.0/8 [1/0] via 2.0.0.2 [1/0] via 7.0.0.2

Thursday, December 6, 2018

Collision & Broadcast domain

Collision domain

A collision domain, as the name implies, is the part of a network where packet collisions can occur. A collision occurs when two devices simultaneously send a packet in the shared network segment. Packages collide and both devices must retransmit packets, which reduces network performance. Collisions are often in a hub environment because each port of a hub is in the same collision domain. In contrast, each port is on a bridge, a power switch, or a router in a separate collision domain.

The following examples illustrate collision domains:




Collision domains

In the above example we have 6 collision domains.

NOTE

Note that each port of a hub is in the same collision domain. Each port on a bridge, power switch, or router is in a separate collision domain.

Broadcast domain

A broadcast domain is the domain to which a broadcast is routed. A broadcast domain contains all devices that can broadcast over the data link layer (OSI Layer 2). All ports on a hub or switch are in the same broadcast domain by default. All ports of a router are in the different shipping domains, and routers do not send mail from one sending domain to another.

The following example illustrates the concept:




Broadcast domains

In the screenshot above, we have three broadcast domains because all ports on a hub or switch are in the same broadcast domain and all ports on a router are in a different broadcast domain.

Monday, December 3, 2018

CCNA 200-125 Exam: IPv6 OSPF Sim With Answers

Question

All routers run IPv6 OSPF with process ID 100. The IPv4 address of Loopback0 is the OSPF router's ID for each router.

A provider connection is located on the HQ router and you must configure a default IPv6 route in HQ and ensure that this route is announced in the IPv6 OSPF process. Also fix the reason why HQ does not make an IPv6 OSPF neighbor with BR.




Requirement:

1. Configure the default IPv6 route on the HQ router with the default gateway for 2001: DB8: B: B1B2 :: 1
2. After configuring the default router in HQ, point the vendor's IPv6 address 2001: DB8: 0: 1111 :: 1
3. Verify that the default box appears in IPv6 OSPF router HQ. This default route should only be notified if HQ has a default route in the roster table
4. Router HQ does not form an IPv6 OSPF neighbor with BR. Solve the problem and solve it

Special Note: To get the maximum number of points, you must complete the necessary configurations and fix a problem with the IPv6 OSPF interface with the BR BR. IPv6 OSPFv3 must be configured without using address families. Do not change IPv6 OSPF Process ID.

Solution

1. Configure the default IPv6 route on the HQ router with the default gateway for 2001: DB8: B: B1B2 :: 1:

(config) # ipv6 unicast routing
(config) # ipv6-route :: / 0 2001: DB8: B: B1B2 :: 1

First, we need to enable IPv6 routing with the command "ipv6 unicast routing" before we configure a default route on the HQ router.

2. Verify by testing the IPv6 address for the 2001 Provider: DB8: 0: 1111 :: 1, after configuring the default route in HQ:

# ping ipv6 2001: DB8: 0: 1111 :: 1

Run the ping test to see if the default pane works. Ping must be successful.
3. Verify that the default box appears in IPv6 OSPF router HQ. This default route should only be notified if HQ has a default route in the schedule table:

(config) # ipv6 router ospf 100
(config-rtr) # default information

The "Default Information Origin" command generates a default route, and is sent to all other routers in OSPF domain, provided that the local router has configured a default route.

4. Router HQ does not form an IPv6 OSPF neighbor with BR. Solve the problem and solve it

Perhaps the interface S1 / 0 of HQ not enabled with IPv6 OSPF (check this with the command "show run" or "show ipv6 OSPF interface").

(config) #interface s1 / 0
(config-if) # ipv6 ospf 100 interval 0

After the configuration, use the ipv6 ospf command command in the main directory to see if BR is specified in the output.

Sunday, November 25, 2018

Introduction to Cisco Catalyst 9200 Switch

Introduction to Cisco Catalyst 9200 Switch

Are you ready to upgrade Cisco Catalyst 2960 X / XR switch to Cisco 9200 Catalyst switch?
Today, November 13, 2018, Cisco announces a new 9200 Catalyst Switch in its Cisco Catalyst 9000 Portfolio, which already contains the Cisco Catalyst 9300, 9400 and 9500 switches. This Catalyst 9200 switch is an upgrade model for Cisco Catalyst 2960 X / XR switches. Cisco announces three different models in the Cisco Catalyst 9200 Switches.

The Cisco Catalyst 9200 Series Changer extends the performance of intentional networks and Cisco Catalyst 9000 hardware and software experience to a wider range of implementations. The Catalyst 9200 Series, with its family artocracy, offers the best catalyst properties of the next generation.

What do you get in the Cisco Catalyst 9200 Switch?
With a capacity of 160 Gbps per stack, you can get 4x1G SFP or 4X10G SFP + ports. Because it replaces the Cisco Catalyst 2960 X / XR switches, you can use the common operating system for switching, routing, wireless and IoT. The low-end access switches are manufactured using the IOS-XE operating system and standard programmable interfaces.


Figure 1.1 - Cisco Catalyst 9200 Switch



The Cisco Catalyst 9200 switches give you the same features as streaming telemetry. Yes, with Cisco Catalyst 2900, replaced by 9200, you can set an access switch in SD Access. XR switches with Cisco 9200 switches in my next article.

What are the different models of Cisco Catalyst 9200?

Cisco comes with the models below.
Catalyst 9200 24 and 48 port, fixed 1G uplink
Catalyst 9200 24- and 48-port fixed 10G uplinks
Catalyst 9200 Modular Uplinks with 24 and 48 ports


Catalyst 9200 24 and 48 port, fixed 1G uplink

For this type, Cisco launches two models with 1G uplink. These models are C9200L-24T / P-4G and C9200L-48T / P-4G. The features are below:
With the Cisco Catalyst 9200 switch, you have all the PoE + options available.
As mentioned earlier, you can get 4 x 1 G SFP uplink ports.
If you have a 48-port switch, you can get up to 48 ports with 30 W full PoE +
At low cost, you can now run SD Access, Cisco StackWise and MACsec
With the unnecessary power supplies and fans and IOS XE features.


Catalyst 9200 24- and 48-port fixed 10G uplinks

Cisco launches two 10G uplink models for this type. These models are C9200L-24T / P-4X and C9200L-48T / P-4X. The features are below:
With the Cisco Catalyst 9200 switch, you have all the PoE + options available.
As mentioned earlier, you can get uplink portals with 4 x 10 G SFP +.
If you have a 48-port switch, you can get up to 48 ports with 30 W full PoE +
At low cost, you can now run SD Access, Cisco StackWise and MACsec
With the unnecessary power supplies and fans and IOS XE features.


Catalyst 9200 24 and 48 port, modular uplinks

Cisco launches two 10G uplink models for this type. These models are C9200L-24T / P and C9200L-48T / P. The functions are below:
With the Cisco Catalyst 9200 switch, you have all the PoE + options available.
As mentioned earlier, you can get 4 x 1/10 G, 2 x 25/40 G modular uplinks
If you have a 48-port switch, you can get up to 48 ports with 30 W full PoE +
At low cost, you can now run SD Access, Cisco StackWise and MACsec
With the unnecessary power supplies and fans and IOS XE features.

Friday, November 23, 2018

Open Shortest Path First (OSPF) Cheatsheet for Free !!!



Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single autonomous system (AS). It is defined asOSPF Version 2 in RFC 2328 (1998) for IPv4.





Monday, November 19, 2018

EIGRP automatic & manual summarization

EIGRP automatic & manual summarization


Route Summary is a method of displaying multiple networks with a single summary URL. It is often used in large networks with many subnetworks, as it reduces the number of routes a router must maintain and minimizes the traffic used to route updates. There are two methods for route summary: automatic summary and manual summary.

EIGRP auto summary

In EIGRP, the automatic summary function is enabled by default. For this reason, routes are grouped into routing updates in class-related addresses at network boundaries.

Consider the following example to better understand the concept of auto summary.




Routers R1 and R2 perform EIGRP. The router R1 has the locally connected subnet 10.0.1.0/24, which is communicated with the router R2. Due to the automatic resume function, the router R1 completes the network 10.0.1.0/24 before the box is sent to R2. If the autoscroll function is enabled, R1 sends the classified route 10.0.0.0/8 to R2 instead of the more specific 10.0.1.0/24 route.

At R1, we have configured the following network declaration:



Due to the auto summary function, R2 gets the route to the 10.0.0.0 / 8 network:



The auto-summary feature can cause problems with non-neighboring networks. Because of this, this feature is usually disabled. This is done with the command no automatic summary:



Now, R2 has the classless way to reach subnet 10.0.1.0/24:



EIGRP manual summary



One of the advantages of EIGRP over some other routing protocols (like OSPF) is that manual resync can be done on any router within a network. A single route can be used to represent multiple routes, reducing the size of routing tables in a network.

The manual summary is configured for each interface. The syntax command is:

(config-if) IP Summary Address Eigrp ASN SUMMARY_ADDRESS SUBNET_MASK

An example helps you understand the concept of manual summary:



Routers R1 and R2 perform EIGRP. The router R1 (left) has two online subnet networks: 10.0.0.0/24 and 10.0.1.0/24. EIGRP announces these subnetworks as two separate routes. R2 now has two routes for two subnetworks that can be confirmed by the show ip-rut command of R2:



We could configure R1 to only announce a summary route for both subnetworks, reducing R2's routing table. The following command can be used for this:




EIGRP Manual Summary

Now R1 only sends one route to reach both subnet to R2. We can verify this with the show ip routing command on R2:



Displays the summary of the IP box manually
Now R2 only has a route to reach both subnet of R1.

Sunday, November 18, 2018

Network Address Translation (NAT) CheatSheet Free !!

Network Address Translation (NAT), you can redirect one IP address space to another by changing the network address information in the IP header of packets during transmission via a traffic redirection device. [1] Originally, this technique was used as an abbreviation to avoid reading any host when a network was moved. It has become a popular and important tool to protect the global address space from the fatigue of IPv4 addresses. An IP gateway IP address for a NAT gateway can be used for a completely private network.

In IP masking, an entire IP address space, usually consisting of private IP addresses, is masked behind a single IP address in another, typically public, address space. The address to be masked is replaced by a single (public) IP address as the "new" source address of the outgoing IP packet. It comes not from masked values, but from the router itself. Due to the popularity of this technology for maintaining the IPv4 address space, the term NAT is almost synonymous with hidden IP.



Saturday, November 17, 2018

EIGRP Configuration

EIGRP configuration


Eigrp configration is very simple to Do you just need some steps to Learn to do Eigrp configration as Given Below:

To enable eigrp on router we need to do two simple steps:

1-Enable Eigrp by command:Router eigrp ASN_Number(Number you want).

Ex:Router Eigrp 10.

2-Advertise the Network you want with or without WildMask as You want.

Ex:Network 10.0.0.0 0.0.0.255(optional Wildcard Mask).

To Illustrate Eigrp Configration i will take Practical in Cisco Packet Tracer.

Their are two Scenario of Eigrp Configration:

1-With Wildcard Mask Given

2-Without Wildldcard Mask Given


Eigrp Configration with WildCard Mask


 Enabling Eigrp on Router 1:



 Enabling Eigrp on Router 2:



Verify Neighbourship using This Command:



That's It Eigrp Configration is Done Now Check Whether Routes are Exchanged or Not as Shown Below:

Router 1


Router 2


Eigrp Configration without WildCard Mask


By Default,he network command uses a classful network as the parameter. All interfaces inside that classful network will participate in the EIGRP process.To enable EIGRP only on specific interfaces, a wildcard mask can be used. 




Verify The Only Network of 10.0.0.X is included in Eigrp :