How Do You Interview A Network Engineer?

vrmlguy asks: "Back in July, we learned how to interview programers, and in August we learned how to interview sysadmins. Obviously, we still need to hire some network engineers, but what questions should we ask? The previous articles had a couple of generic gems which I intend to put to good use, but the only position-specific question that I can come up with is "Please explain the differences between RIP and OSPF." Any other ideas for a guy whose idea of using a sniffer is to fire up tcpdump?"

Comments

background, breadth

[green pizza]

Has the person worked with enough types of networking gear to understand the history, future, and direction so that he can make informed decisions as new products become available? Having only worked with ethernet is a bad sign.

Has he worked with powerful software tools, both commercial and opensource? (HP Openview, CA Unicenter, etc).

What is his experience with router equipment? Experience with at least one other large scale platform other than Cisco is a huge plus.

Re:background, breadth

[Anonymous Coward]

ROFL!

When I read the post title, the nick blended with it in my head and I read "background, pizza breath". Thought you were going to recommend checking their geek quotient by smelling their breath...

Well

[_typo]

Actualy the best way is to post a link to your public webpage on slashdot saying it's some sort of geek gadget/website and then let him scramble trying to get the site to live the DDoS.

Well, not really, I guess I'd look for:

- Experience in Unix (You'll need it if your serious about networking)

- Experience in seting up the stuff you need and use, may they be BGP, IP, TCP or higher level stuff like network services

- Knowledge of available hardware from the major manufacteurs and what he whould use to solve particular problems (make up some situations)

- Availability to be paged at any hour (night or day) since stuff always fails at 4 am on a Saturday

- Personality/Friendlyness ???

Of course if you already have network guys around ask them to inverview candidates and let them choose.

One fat question...

[RadioheadKid]

If the candidate thinks Cisco is that white lard stuff you put on your baking pans, he's probably not ready for the job...

But seriously, I think scenario based questions are great, like this doesn't work, what are the steps you would take to trouble-shoot it. Or given this budget, and bandwidth requirements, etc..what would you set up in this situation. And it depends on the nature of the job what areas to focus on. It also helps you find out if this person is going to b.s. you or not. I'd rather have someone say, well I'm not sure, than jump in the deep end with no way to swim out. Hope that helps...

What's the best way to learn old networking stuff?

[cymen]

In a similar vain what is the best way to learn older networking stuff like token ring? I recently had a friend ask me if I could help her public school with their ailing token ring network. But because I have no experience with tokent ring I couldn't help her.

Obviously I'm going to buy a couple of old token ring cards to play with but are there any good sites for background information, etc? I don't expect to become a networking guru but learning more about not so common network equipment would be interesting...

Ask them to draw pictures, ask some dumb questions

[indaba]

I'm a network engineer and I live with a whiteboard marker in my hand.

So , ask them to draw you some pictures. Like:

OSI model

Operation of at least 2 IGP's , ie OSPF, RIP, EIGRP

Route redistribution

Spanning tree

Multicasting

Split horizon

etc .. you get the idea

Ask a few dumb questions :

what's ARP ?

difference between a router and a switchname me a layer 4 IP protocol

what does NAT do ?

who's Jon Postel ?

who's Vint Cerf ?

what's the IETF ?

whats an RFC ?

etc .. you get the idea

Finally, if you have the time, give them 2 routers and switch
Get him/her to configure :

PPP, and CHAP

RIP, or OSPF or EIGRP

IPX

a simple access-list

basic router authentication

etc .. you get the idea

Also, certifications DO help you weed out the rubbish.

Darren Kruse CCNP CCDP
WAN/LAN Networking Consultant
Email : darren_kruse@hotmail.com
www.geocities.com/darren_kruse

ps, I'm alway's looking for work :-)
here at eBay !

interview questions

[DNS-and-BIND]

I advocate preparing a bunch of trick questions in advance. The answers you expect don't have to be particularly accurate, indeed they can be downright wrong. What's important is not to test the basic skills of the interviewee, but to fellate the ego of the interviewer by demonstrating superior knowledge of inane trivia like obscure, special-purpose cisco patches.

At least, that's what I've come out of interviews thinking.

depends on job

[twigman5000]

You can't judge netadmins by sysadmin standards. Asking about opensource software is only relevant in terms of management stuff like Openview (not open) or protocols like OSPF and VRRP (HSRP for Foundry).
Some good questions are: difference between OSPF & EIGRP
What ports to block at the border inbound and ourbound
What's an AS?
What's a looking glass?
Maximum number of load-balancing paths in OSPF
Explain STP
Explain routing between VLANs

THis is stuff I can explain off the top of my head and I've been concentrating on host stuff for a few months now, so any decent candidate should get em.

test

[cr0sh]

this is a test - please ignore or mod down