NETWORKING INTERVIEW QUESTIONS - 2

What is difference between Login and Login Local command in Cisco IOS?

Attempt to login to the router LOGIN command ask only password.

Router (Config) # line vty 0 4

Router (Config-line) #password 1234

Router (Config-line) #Login

Attempt to login the router LOGIN LOCAL command ask username and password (Stored

locally on Cisco IOS)

Router (config) # username cisco password 123

Router (config) # username networking password 123

Router (Config) # line vty 0 4

Router (Config-line) #Login local

can I upgrade IOS or upload IOS images through USP Port? 

Yes, the newer or other switches with USB type A Port you can use USB 

port and upload from the thumb drive .

Notes:Thumb drive must be FAT-16- Formatted.

copy flash file in to thumb drive.

Router# show version

Check which IOS file is running now.

Router# show usbflash1

It will show the list of file in thumb drive

Flash file in bin format.

Router#copy usbflash1:<IOS file name> flash

........

copied to flash

now

Router#show  flash

list of files in the flash

(old IOS file and NEW IOS file will show)

 Router# config t

Router(Config)# boot system flash <new IOS file name>

Router(Config)#exit

Router#reload.

after reload once verify it with the help of show version command.

now its loaded with new IOS.

two Internet connections I want to share the bandwidth for our users. the

basic requirement for a load balancing solution at the customers site is it possible?

It is possible to configure Load balancing between to static route.

I added two default routes to the two ISP routers

IP route 0.0.0.0 0.0.0.0 Ethernet0/0 129.40.253.1

IP route 0.0.0.0 0.0.0.0 Ethernet0/0 129.40.253.2

Two Switches configure with access port and VLAN 10 in switch 1 and VLAN 20 in

Switch 2 it will communication both the VLAN?

YES. Because all the ports are access port.

EIGRP Default delay micro seconds?

Ten micro seconds.

OSPF Which one is elected first DR or BDR?

BDR first and DR second.

OSPF how many process id can configure?

65535

Different between neighbors and Adjacency in OSPF?

In short, two OSPF routers are neighborsif they are connected to the same subnet and share a series of common configuration information:

• Same Area ID, Same Area type,Same subnet mask,Same timers,Same authentication
• They see their own OSPF RID in each other's Hello packet

In essence, OSPF neighborhood is a relation of two routers that allows them to see and understand each other but nothing more. In particular, two OSPF neighbors do not exchange any routing information - the only packets they exchange is Hello packets.

OSPF adjacency is formed between selected neighbors and allows them to exchange routing information. So, two routers must first be neighbors, only then they can become adjacent. Two routers become adjacent if:

• At least one of them is DR or BDR (on multi access type networks), or
• They are interconnected by a point-to-point or point-to-multipoint network type

In order to minimize the amount of information exchange on a particular segment, OSPF elects one router to be a designated router (DR), and one router to be a backup designated router (BDR), on each multi-access segment.

The idea behind this is that routers have a central point of contact for information exchange. Instead of each router exchanging updates with every other router on the segment, every router exchanges information with the DR and BDR. The DR and BDR relay the information to everybody else. The following router model illustrates the DR and BDR:

In order to distinguish what kind of relation (neighbor or adjacency) you can see 'sh ip ospf neighbor'

R7# show ip ospf neighbor
Neighbor ID     Pri       State           Dead Time   Address         Interface
170.170.3.4       1       2WAY/DROTHER    00:00:34    170.170.3.4     Ethernet0
170.170.3.3       1       2WAY/DROTHER    00:00:34    170.170.3.3     Ethernet0
170.170.3.8       1       FULL/DR         00:00:32    170.170.3.8     Ethernet0
170.170.3.2       1       FULL/BDR        00:00:39    170.170.3.2     Ethernet0

State : FULL/DR or FULL/BDR means the adjacency is FULL with the DR and BDR (Note an adjacency is established by all routers of the multiaccess segement/NBMA with DR and BDR).

For those which are 2WAY/DROTHER means a neighbor relationship.