Michael W. Lucas has been writing technical books for a long time, drawing on his experience as both a system and a network administrator. He has mastered the art of making it both easy and enjoyable to inhale large amounts of information; that's my way of saying he writes books well and he's a funny guy. "Networking for System Administrators", available both in DRM-free ebook and dead tree formats, is his latest book, and it's no exception to this trend.
Like the title suggests, this book explains networking to sysadmins — both juniors new to this career, and those who have been around for a while but don't understand how those network folks live or what they need to do their job. If you're one of the latter, you might think "Oh I've read 'TCP/IP Illustrated' — I don't need another networking book." And it's true that there is overlap between these two books. But Lucas also explains about how to work with network folks: dealing with areas of shared responsibility, how to understand where your side ends, and how to talk to a network admin so that everyone understands each other — and more importantly, is both able and happy to help the other. This is something that is out-of-scope for a network textbook, and it's valuable.
So what's in this book? Lucas takes us through all the network layers, explaining how everything fits together. From physical ("If you can trip over it, snag it, break the stupid tab off the plastic connector at its end, or broadcast static over it, it's the physical layer.") to transport and application, he shows practical examples of how the OSI model maps (or doesn't) to the world of TCP/IP. He shows the happy path and the sad path at each layer, explaining how to understand what's going on and troubleshooting failures. This is the part with the strongest overlap with those other network textbooks. If system administration is a side gig (maybe you're a developer who has to maintain your own server), you'll have enough in this book to deal with just about anything you're likely to trip over. But if you're early in your sysadmin career, or you find yourself making the jump to Ops, you will want to follow it up with "TCP/IP Illustrated" for the additional depth.
Since you'll be troubleshooting, you'll need to know the tools that let you dump DNS, peer into packets, and list what's listening (or not) on the network. Lucas covers Linux and Unix, of course, but he also covers Windows — particularly handy if, like me, you've stuck to one side over the course of your career. Tcpdump/Windump, arp, netstat, netcat and ifconfig are all covered here, but more importantly you'll also learn how to understand what they tell you, and how to relay that information to network administrators.
That thought leads to the final chapter of this book: a plea for working as a team, even when you're not on the same team. Bad things come from network and systems folks not understanding each other. Good things — happy workplaces, successful careers, thriving companies and new friends — can come from something as simple as saying "Well, I don't know if it is the network's fault...why don't we test and find out?"
After reading this book, you'll have a strong footing in networking. Lucas explains concepts in practical ways; he makes sure to teach tools in both Unix/Linux and Windows; and he gives you the terms you'll use to explain what you're seeing to the network folks. Along the way there's a lot of hard-won knowledge sprinkled throughout (leave autonegotiation on — it's a lot better than it used to be; replace cables if there's any hint of flakiness in a server's network connection) that, for me at least (and be honest, you too) would have saved a lot of time over the years.
Who would I recommend this book to?
- If you're a sysadmin at the beginning of your career, this book is an excellent beginning; take it, read it, and build on it — both with practical experience and further reading.
- If you're coming into system administration the back way (as a developer who has to manage their own server, say, or who shares responsibility for a networked service with other admins), I can't think of a better single source for the practical knowledge you need. You'll gain an understanding of what's going on under the hood, how to diagnose problems you encounter, and how to talk to either system or network administrators about fixing those problems.
- If you're a manager or senior sysadmin, buy this book and read it through before handing it to the juniors on your team, or that dev who keeps asking questions about routing and the firewall; you may learn a few things, and it's always good to read fine technical writing.