General Areas to Prepare for interview
OSPF
Describe OSPF in your own words.
OSPF areas, the purpose of having each of them
Types of OSPF LSA, the purpose of each LSA type
What exact LSA type you can see in different areas
How OSPF establishes neighboor relation, what the stages are
If OSPF router is stucked in each stage what the problem is and how to troubleshoot it
OSPF hierarchy in the single or multi areas. Cool OSPF behavior in broadcast and nonbroadcast
Draw the diagram of typical OSPF network and explain generally how it works, DR, BDR, election, ASBR, ABR, route redistribution and summarization
STP
How it works and the purpose
Diff types (SSTP, MSTP, RSTP) Cisco - PVST/PVST+
root election
Diff. port stages and timing for convergence
Draw the typical diagram and explain how diff types of STP work
What ports are blocking or forwarding
How it works if there are topology changes
ACLs
What are they
Diff types
Write an example if you want to allow and to deny…
Well-known port numbers (DNS - 53 and etc…)
QOS
What is that
What is the diff b/w L2 and L3 QoS
How it works
Network:
Draw the typical network diagram you have to deal with
explain how it works
What part of it you are responsible
firewall, what is that, how it works, how it is diff from ACLs
What problems with the network you had had and how you solved it.
What are the ways to troubleshoot the network, techniques, commands
network security, ways to achieve it
Switching:
VLANs
STP
How a L2 switch works with broadcast, unicast, multicast, known/unknown traffic
VRRP, GLBP
port monitoring and mirroring
L3 switch, how it works
PIM sparse and dense mode