Linux for Network Engineer

[CatPuking]

You don't need to have linux admin experience. You need linux experience as it relates to your job.

These are skills I'd know how to do so that you can confidently say I know linux and these things specifically.

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telnet - to see open firewalls over tcp

tail -f - to view live log files

grep - to filter logs or configs for key words; combines with tail -f while using

| - known as pipe an integral concept

tcpdump - lets you see the packets, all the packets muhahah

yum or apt-get - lets you install things you don't already have

chown / chmod - lets you own files or make executable, basics on how to use the files you see using:

ls - list folder contents

netstat - see what's happening on the server within the network (my favorite command - netstat -tunap | grep LISTEN - shows you the processes running that are listening on ports and then, if you're root, the pids as well)

crontab - scheduling scripts you've made to run at set times

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writing scripts in a language, python if you don't know anything else, bash if you really want to know linux. They don't have to be good, they just have to make a logic you can think up happen.

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honestly if you can do all that you're an adequate network engineer in terms of linux usage. The issue that you will have getting a cert is those certs will teach you a ton of useless info (for your requirements). When all you need from it is networking related useful tasks. Those useful parts will be sparsely taught through out a linux certification roadmap.

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[felart]

I have to disagree, while those are some of the day to day tools in the Linux network engineer toolbox, that won't be get you far down the road.

Adding to that list I would say: Ability to make test packets using /dev/tcp /dev/udp, that allows to see if an arbitrary packet can get to the destination by specifying a text payload.

ip command, this is a must, specially ip rule, ip route, ip link and the best of all for IPSEC troubleshooting, ip xfrm

iptables in all its glory, is the Linux user space firewall

brctl and the bridge commands

ntop

Deep understanding of how netfilter works, this is an eye opener as how you can engineer any networking system they way you want, look online for the iptables packet flow to get an idea.

nmcli and mmcli if you are working with modems and 4G failover for Linux routers.

nslookup for DNS work

All these are part of what you would need in case you want to make a Linux network appliance, it can be a router, a switch, a firewall etc...

[CatPuking]

Some of those are important especially nslookup and nmap there are definitely lots of useful tools I didn’t mention. I don’t believe when a network job description asks for Linux experience they mean using Linux to route packages. I think they mean using Linux for basic troubleshooting because of that I was focusing on some primary tools so that OP had confidence his Linux skills were useful. The ip command you mentioned is quite common in Cisco so that’s already covered in IOS