Eric Stewart: Running Off At The Mouth

ISC DHCP – “subnet” vs “pool” Declarations

by on Aug.08, 2014, under Networking, Technology

We ran into a little issue that, while others might think it simple, we had never seen before. A client requests a reserve lease; once the lease is provided, their PC wasn’t getting a gateway address. Here’s why (as far as I know at this time).

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Nexus 7700 Part III: Breakout Interfaces

by on Jul.15, 2014, under Networking, Technology

It is possible on the Nexus 7700 line, with certain optics, to break out 40Gb (and eventually 100Gb) to 4x10Gb interfaces (no one knows for sure what 100Gb will do – it will either be 8x10Gb or 10x10Gb). In this post I go over how $JOB is doing it (at least with the 40Gb) and what you need to be aware of. I do touch a little bit on the 100Gb breakout future and explain why we were looking to do it.

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Nexus 7700 Part II: Racking a Cisco Nexus 7710

by on Jul.08, 2014, under Networking, Technology

We racked our Nexus 7710 recently. Here’s some of the things you might need to know regarding getting this monster of a chassis into a rack.

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So I Went To My Second Cisco Live …

by on Jun.25, 2014, under Life, Networking, Technology

I figured I should get this written while I can, and before it all fades away from my brain … here’s my thoughts on Cisco Live and some advice for future first-time attendees.

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Nexus 7700 Part I: Power and Playing With Supervisors

by on Jun.23, 2014, under Networking, Technology

So we powered on our first to arrive Nexus 7706s (two of them). Here’s some notes so far.

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Nagios’s check_ntp_peer, IPv6, and ntp.conf

by on Jun.03, 2014, under Networking, Technology

As is not unusual, I run into an edge case that might be specific to us. While attempting to monitor IPv6 reachability of an NTP server I had just upgraded, I ran into an interesting case where NTP was responding via IPv4, but not IPv6, and they appeared to be identically configured.

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Air Travel

by on May.16, 2014, under Life

Quick post about how to get your way through airline security without wasting everyone else’s time.

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Restarting iptables and MySQL slave connections

by on Feb.27, 2014, under Networking, Technology

It’s been a while since I’ve done more than just update the Unified Trees post for new versions, and I stumbled across an issue that Linux administrators that make use of iptables should be aware of. The case is actually true for any “client initiated connection” when it comes to iptables – not just MySQL slaves. That’s just where I stumbled across the issue.

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Unified Trees 0.8: Cacti Plugin

by on Dec.06, 2013, under Networking, Technology

Got multiple Cacti installs? Want the Tree view of your graphs to show all of your trees mashed together? Then this is the plugin for you.

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DPDiscover 1.45: Cacti Plugin

by on Nov.14, 2013, under Networking, Technology

I wrote a Cacti plugin I called DPDiscover – Discovery Protocol Discover, which uses LLDP, CDP, and FDP information pulled from SNMP to ‘spider’ a network and attempt to automatically add equipment to Cacti. It is heavily based off of the original “Auto Discovery” plugin that would sweep IP ranges.

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