Network Troubleshooting interview questions

The following network troubleshooting interview questions is a sample preview from the Ebook – 250 + Network engineer interview questions and answers

Buy from Amazon

A network administrator incorrectly configures manually the DNS server IP address on the clients TCP/IP adapter setting. The default gateway of the network which is the internet router has the correct DNS entry in its configuration. The clients IP address, subnet mask and the default gateway information is provided by the DHCP server on the router. Would the client be able to browse?

a) The client will not be able to browse
b) The client would send the webpage request to the router and it would use the router as a proxy
c) It would have been possible for the client to browse if the routers IP address was provided in proxy configuration in the browser.
d) The client ignores the DNS IP address setting on the TCP/IP adapter configuration as it accepts its IP address from the DHCP server and would be able to browse irrespective of the incorrect configuration.

An open office measuring an area of 1000 sqft has wireless access points operating in 802.11 g mode. The total number of access points in the room is 4. Users start to complain that they lose connectivity occasionally. What could be the issue?

a) Users wlan radio would be operating in 802.11 b mode
b) Overlapping channels in wireless access points
c) Reauthentication issue with users encryption keys
d) More access points required to cover the required area.

Ebook – Wireshark Tutorials for Network Administrators

A network administrator has been asked to deploy a DHCP server on the network to migrate from static to dynamic IP address setting on users. After the deployment the users started to complain about unavailability of internet. What could be the possible reason?

a) The DHCP Servers domain name would not have been registered on the network
b) DHCP Server created a broadcast storm which made the internet unavailable to the users
c) DNS Server IP address was not configured as a DHCP server options field.
d) A route from the DHCP server was not configured to communicate with the internet router

A user in the company network complains that he is unable to connect to a FTP server on the internet. The user attempts to connect to the internet FTP server through a network layer firewall. The FTP server and client use Active FTP protocol. What could be the possible issue?

a) Data and control port for the FTP server is not configured on the firewall
b) Dynamic ports for connecting to the client from the FTP server is not configured on the firewall
c) Network layer firewall does not understand FTP which is an application layer protocol
d) This is a limitation with Active FTP and firewalls.

A network consultant deploys a network with 2 ethernet switches interconnected to each other with two physical links. After deployment, the company administrator provided IP addresses to the clients ( 20 PC’s on swicth1 and 20 PC’s on switch 2 )but accidentally provides an incorrect default gateway (Non existent IP address) for the users. After some time the administrator observes that LED of 2 switches starts flashing and the link is broken. What is the root issue?

a) The incorrect default gateway
b) Layer 2 loop
c) Rate limit on internet traffic on switch interconnected ports not configured
d) Multicast traffic not handled efficiently

A tech support engineer has a case which needs to be resolved at the earliest. Details below

1.Customer is able to ping the default gateway from the PC (default gateway IP is home router LAN IP address)
2.Customer is able to ping its DNS server which is also the default gateway from the PC.
3.Customer is unable to ping IP address of servers on the internet (Ex: IP address of from the PC.
4.Customer is able to ping servers on the internet from the default gateway (Home router console)
5.Customers TCP/IP address setting:

IP Address:
Subnet Mask:
Default Gateway:
DNS Primary:
DNS Secondary:
Default Gateway IP address

What is the cause for point 3?

a) Incorrect primary DNS IP address
b) Proxy information should be provided for internet ping request
c) Default gateway incorrect in TCP/IP setting
d) Route entry missing on the TCP/IP settings provided

Buy and Download the Ebook – 250+ network Engineer interview questions and answers for the answers and detailed explanation

Buy from Amazon

Ebook Store – Click Here