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Sysadmin and Networking ;login APRIL 2014 VOL. 39, NO. 2 : Sysadmin and Networking & SDN, Beyond the Hyperbole Rob Sherwood & The Case of the Clumsy Kernel Brendan Gregg & System Administration Is Dead Todd Underwood & I Am Not a Sysadmin Elizabeth Zwicky & Splunk Performance Tuning David Lang Columns Practical Perl Tools: Using MongoDB David N. Blank-Edelman Python: When to Use Python 3 David Beazley iVoyeur: ChatOps Dave Josephsen For Good Measure: Mitigation as a Metric Dan Geer and Richard Bejtlich /dev/random: I Miss Being a Sysadmin Robert G. Ferrell UPCOMING EVENTS 2014 USENIX Federated Conferences Week CSET ’14: 7th Workshop on Cyber Security June 17–20, 2014, Philadelphia, PA, USA Experimentation and Test August 18, 2014 HotCloud ’14: 6th USENIX Workshop on www.usenix.org/cset14 Hot Topics in Cloud Computing Submissions due: April 25, 2014 June 17–18, 2014 www.usenix.org/hotcloud14 3GSE ’14: 2014 USENIX Summit on Gaming, Games, and Gamification in Security Education HotStorage ’14: 6th USENIX Workshop August 18, 2014 on Hot Topics in Storage and File Systems www.usenix.org/3gse14 June 17–18, 2014 Invited submissions due: May 6, 2014 www.usenix.org/hotstorage14 FOCI ’14: 4th USENIX Workshop on Free and Open 9th International Workshop on Feedback Computing Communications on the Internet June 17, 2014 August 18, 2014 www.usenix.org/feedbackcomputing14 www.usenix.org/foci14 WiAC ’14: 2014 USENIX Women in Advanced Submissions due: May 13, 2014 Computing Summit HotSec ’14: 2014 USENIX Summit on Hot Topics June 18, 2014 in Security www.usenix.org/wiac14 August 19, 2014 ICAC ’14: 11th International Conference on www.usenix.org/hotsec14 Autonomic Computing HealthTech ’14: 2014 USENIX Summit on Health June 18–20, 2014 Information Technologies www.usenix.org/icac14 Safety, Security, Privacy, and Interoperability USENIX ATC ’14: 2014 USENIX Annual Technical of Health Information Technologies Conference August 19, 2014 June 19–20, 2014 www.usenix.org/healthtech14 www.usenix.org/atc14 Submissions due: May 9, 2014 UCMS ’14: 2014 USENIX Configuration Management WOOT ’14: 8th USENIX Workshop on Offensive Summit Technologies June 19, 2014 August 19, 2014 www.usenix.org/ucms14 www.usenix.org/woot14 URES ’14: 2014 USENIX Release Engineering Summit June 20, 2014 OSDI ’14: 11th USENIX Symposium on Operating www.usenix.org/ures14 Systems Design and Implementation October 6–8, 2014, Broomfield, CO, USA 23rd USENIX Security Symposium www.usenix.org/osdi14 August 20–22, 2014, San Diego, CA, USA Abstract registration due: April 24, 2014 www.usenix.org/sec14 Co-located with OSDI ’14: Workshops Co-located with USENIX Security ’14 Diversity ’14: 2014 Workshop on Supporting Diversity EVT/WOTE ’14: 2014 Electronic Voting Technology in Systems Research Workshop/Workshop on Trustworthy Elections October 5, 2014 August 18–19, 2014 HotDep ’14: 10th Workshop on Hot Topics in www.usenix.org/evtwote14 Dependable Systems USENIX Journal of Election Technology October 5, 2014 and Systems (JETS) INFLOW ’14: 2nd Workshop on Interactions of NVM/ Published in conjunction with EVT/WOTE Flash with Operating Systems and Workloads www.usenix.org/jets October 5, 2014 TRIOS ’14: 2014 Conference on Timely Results in Operating Systems October 5, 2014 twitter.com/usenix www.usenix.org/youtube www.usenix.org/gplus Stay Connected... www.usenix.org/facebook www.usenix.org/linkedin www.usenix.org/blog APRIL 2014 VOL. 39, NO. 2 EDITOR EDITORIal Rik Farrow 2 Musings Rik Farrow [email protected] COPY EDITORS Steve Gilmartin OPINION Amber Ankerholz 6 The Death of System Administration Todd Underwood PRODUCTION MANAGER Michele Nelson SYSADMIN PRODUCTION 10 Interview with John Looney Rik Farrow Arnold Gatilao Casey Henderson 14 How to Be a Better System Administrator and Then TYPeseTTER Something Else Elizabeth Zwicky Star Type [email protected] 16 Accelerating the Path from Dev to DevOps Dinah McNutt USENIX AssOCIATION 19 Interview with Tom Hatch Rik Farrow 2560 Ninth Street, Suite 215, Berkeley, California 94710 21 The Case of the Clumsy Kernel Brendan Gregg Phone: (510) 528-8649 FAX: (510) 548-5738 26 Large Scale Splunk Tuning David Lang www.usenix.org 31 /var/log/manager: Let’s Find Someone to Blame Andy Seely ;login: is the official magazine of the USENIX Association. ;login: (ISSN 1044-6397) is published bi-monthly by the USENIX NETWORKING Association, 2560 Ninth Street, Suite 215, 34 SDN Is DevOps for Networking Rob Sherwood Berkeley, CA 94710. 38 Musings and Hacks on DHCP Doug Hughes $90 of each member’s annual dues is for a subscription to ;login:. Subscriptions for non- members are $90 per year. Periodicals postage COLUMNS paid at Berkeley, CA, and additional offices. 43 Practical Perl Tools: MongoDB Meet Perl POSTMASTER: Send address changes to ;login:, USENIX Association, 2560 Ninth Street, David N. Blank-Edelman Suite 215, Berkeley, CA 94710. 47 A Pragmatic Guide to Python 3 Adoption David Beazley ©2014 USENIX Association USENIX is a registered trademark of the 52 iVoyeur: ChatOps Dave Josephsen USENIX Association. Many of the designations used by manufacturers and sellers to 58 Measure Like You Meant It Dan Geer and Richard Bejtlich distinguish their products are claimed as trademarks. USENIX acknowledges all 61 /dev/random: Robert G. Ferrell trademarks herein. Where those designations appear in this publication and USENIX is aware of a trademark claim, the designations have BOOKS been printed in caps or initial caps. 63 Book Reviews Elizabeth Zwicky, Rik Farrow, and Mark Lamourine Musings RIK FARROWEDITORIAL Rik is the editor of ;login:. have a new hat, one with a fancy feather in it, perhaps to help it feel lighter. [email protected] I’ve become the tutorial manager, taking over for Dan Klein after he’s I done the job single-handedly for more than 20 years. I appreciate what Dan has done and will have to work hard, working with a team, to do as well and, hopefully, better. This change has led me on a quest for information about the future of system administration. What I learned is nothing new, in a way: system administration has always been changing. But, as always, there will be the risk takers, the early adopters, and the adventurers—the ones who strike out in new directions expecting that others will surely follow them. There are also those who, having been through several schools of hard knocks, would like to continue on the path that they have become adept at navigating. Those hard knocks were painful and time-consuming, and learning new ways of doing things means going through yet another learning process. Being an older kind of guy, I too can resist change. Then again, I know it’s good for the ol’ noggin to stretch its limits by learning new things. I’ve watched what being really stuck does to older folks than I, and I surely don’t want to go there. System Administration, Then and Now Like Elizabeth Zwicky writes in this issue, I am not a system administrator. Oh, I can still fake it, by managing my own systems (DNS, SMTP, DHCP, and HTTP) and occasionally even consulting locally. But I gave up on being a sysadmin when I found out that I wasn’t very interested in a very important aspect of it: building scripts and systems to automate the work that needed to be done routinely. What I liked most about being a sysadmin was solving problems. Although my skills are dwarfed by Brendan Gregg (also in this issue), I followed one of the techniques in his book [1], the scientific method. I didn’t learn it from his book, but from Arthur Conan Doyle’s fictional detective, Sherlock Holmes. I read all the stories about Sherlock, and what stuck with me was a methodical approach to problem solving: gathering evidence, creating a hypothesis, testing it, then either fixing the problem or iterating, depending on the result. I think I also liked the effect I could have on people when I produced wizard-like successes. Often, simply by creating a clear problem statement, the answer to the problem would just pop out. I liked feeling and appearing smart. What I didn’t like was the boredom of repetition: adding a user to a handful of workstations or performing updgrades on that same set of systems. Like Elizabeth Zwicky, I am not a programmer who builds systems from scratch. So I contented myself with fixing systems, sometimes by building scripts for specific purposes. Managing a group of systems through a unifying set of programs, however, was beyond my thinking. I gradually drifted away from system administration. 2 APRIL 2014 VOL. 39, NO. 2 www.usenix.org EDITORIAL Musings For most of the ’90s, system administration remained very administrators are going to need new skills so they can work similar to what I had experienced. People managed each system with online services. Debugging a distributed system where you separately, perhaps leveraging some network software (like NIS have access to both the networks and the servers is very different or LDAP) to solve part of the management issues. Someone who from troubleshooting a distributed application running in the managed a lot of systems, say one or two hundred, would do so by cloud where your access is limited. And working at scale, even making them all look exactly alike, whether they were part of a modest scales, means the end of manually searching logs and cluster or developer desktops. monitoring: you need automation to help not just pick up prob- lems but respond to them appropriately, and in a timely manner. Configuration management brought about some real changes, allowing administration of more systems without the need to Will every service move to a cloud? I don’t think the NSA is make them all the same: now we could have groups of systems, going to, and neither will privacy-sensitive or regulatory-bound and systems with sets of software on them.
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