Five selfish reasons to interview candidates
Lets be honest. It is hard to justify the time needed to interview people. It can be really hard to motivate yourself to interview potential new hires when project deadlines are looming. It is perfectly fair to ask yourself, “what’s in it for me?” I think there is a payoff for time spent on hiring. […]
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The post Five selfish reasons to interview candidates appeared first on Packet Pushers Podcast and was written by John Harrington.
NFD6 Preview: Solarwinds
You can’t really be in the networking industry without hearing about Solarwinds. Their IT management and monitoring products are very widely used. Nearly every customer I’ve worked with is using Solarwinds’ tools to some extent, whether it’s the ever-popular Orion NCM for network management and monitoring, or the slew of free tools that Solarwinds makes available for little troubleshooting or configuration tasks. Solarwinds has supported NFD for quite some time. At NFD5, they presented on quite a few things.NFD6 Preview: Solarwinds
You can’t really be in the networking industry without hearing about Solarwinds. Their IT management and monitoring products are very widely used. Nearly every customer I’ve worked with is using Solarwinds’ tools to some extent, whether it’s the ever-popular Orion NCM for network management and monitoring, or the slew of free tools that Solarwinds makes available for little troubleshooting or configuration tasks. Solarwinds has supported NFD for quite some time. At NFD5, they presented on quite a few things.Finding a New Path (Part 1)
In my last installment on the topic of fast convergence, I said I’d be discussing the calculation stage of fast convergence next. Orhan tried to scoop me in the comments, but that’s okay –I’m working at this through the process switched path, rather than interrupt context. In parallel with flooding information about the topology change […]
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Show 161 – VMware NSX – Real World SDN – Sponsored
Deep diving on VMware NSX ? You bet. Download the PDF file and read along with us as we unpack how VMware NSX works with Brad Hedlund and Scott Lowe. Network Virtualization is the certainly the biggest architecture shift in our careers and probably yours. And make no mistake, this is about networking. Greg Ferro often says that […]
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The post Show 161 – VMware NSX – Real World SDN – Sponsored appeared first on Packet Pushers Podcast and was written by Greg Ferro.
Need more capacity: MPC4e cards are there!
Recently, we received in LAB 2 new MPC cards: - The MPC4e Combo card: 2x100GE + 8x10GE ports (MPC4E 3D 2CGE+8XGE) - The MPC4e 32x10GE ports (MPC4E 3D 32XGE) These 2 new cards need at least the Junos 12.3 and can be used on both dense chassis: MX960 and...Need more capacity: MPC4e cards are there!
Recently, we received in LAB 2 new MPC cards: - The MPC4e Combo card: 2x100GE + 8x10GE ports (MPC4E 3D 2CGE+8XGE) - The MPC4e 32x10GE ports (MPC4E 3D 32XGE) These 2 new cards need at least the Junos 12.3 and can be used on both dense chassis: MX960 and...How bad is the OSPF vulnerability exposed by Black Hat?
I was asked a few weeks ago by our field engineers to provide a fix for the OSPF vulnerability exposed by Black Hat last month. Prima facie there appeared nothing new in this attack as everyone knows that OSPF (or ISIS) networks can be brought down by insider attacks. This isnt the first time that OSPF vulnerability has been announced at Black Hat. Way back in 2011 Gabi Nakibly, the researcher at Israel’s Electronic Warfare Research and Simulation Center, had demonstrated how OSPF could be brought down using insider attacks. Folks were not impressed, as anybody who had access to one of the routers could launch attacks on the routing infrastructure. So it was with certain skepticism that i started looking at yet another OSPF vulnerability exposed by Gabi, again at Black Hat. Its only when i started delving deep into the attack vector that the real scale of the attack dawned on me. This attack evades OSPF’s natural fight back mechanism against malacious LSAs which makes it a bit more insidious than the other attacks reported so far.
I exchanged a few emails with Gabi when i heard about his latest exposé. I wanted to understand how this attack Continue reading
Plumbing OpenBSD Software with gdb(1)
This post is about finding and fixing a memory leak I discovered in the SNMP daemon, snmpd(8), in OpenBSD. This sort of analysis is foreign territory for me; I’m not a software hacker by day. However, using instructions written by Otto Moerbeek as my Rosetta stone and Google to fill in the blanks when it came to usage of the GNU debugger, gdb(1), I was able to find and fix the memory leak.
I’m documenting the steps I used for my future self and for others.
The Problem
When walking the pfTblAddrTable in the OPENBSD-PF-MIB, the unprivileged snmpd process would grow in terms of SIZE and RES. Querying other parts of PF-MIB or other MIBS altogether resulted in no memory usage increase.
Since I knew roughly which code path must have the leak, I first examined it manually. I could not see where memory wasn’t being given back. I needed to instrument the process as it was running in order to find the leak.
Before Starting
This set of instructions from Otto Moerbeek was my guide. As per his guide, you have to rebuild libc with MALLOC_STATS enabled. This enables statistics collection that is used later on.
Edit /usr/src/lib/libc/stdlib/malloc. Continue reading
Plumbing OpenBSD Software with gdb(1)
This post is about finding and fixing a memory leak I discovered in the SNMP daemon, snmpd(8), in OpenBSD. This sort of analysis is foreign territory for me; I'm not a software hacker by day. However, using instructions written by Otto Moerbeek as my Rosetta stone and Google to fill in the blanks when it came to usage of the GNU debugger, gdb(1), I was able to find and fix the memory leak.
I'm documenting the steps I used for my future self and for others.
NFD6 Vendor Preview: Nuage Networks
Nuage Networks is making an appearance at both Network Field Day 6 and the Software-Defined Datacenter Symposium the day before. Nuage is new to me, but after perusing some of their literature, I was very comfortable with some of the concepts. First, you’ll recognize the three-tier architecture that’s being used in most SDN discussions in most of their visuals (data plane / controller / NB API) Nuage uses an product called the VSD (Virtual Services Directory) to define network policies and business logic integration.NFD6 Vendor Preview: Nuage Networks
Nuage Networks is making an appearance at both Network Field Day 6 and the Software-Defined Datacenter Symposium the day before. Nuage is new to me, but after perusing some of their literature, I was very comfortable with some of the concepts. First, you’ll recognize the three-tier architecture that’s being used in most SDN discussions in most of their visuals (data plane / controller / NB API) Nuage uses an product called the VSD (Virtual Services Directory) to define network policies and business logic integration.Professional Loneliness
Lately I’ve been bouncing some generic DMVPN questions off the twittersphere. I’ve used DMVPN sporadically in tiny single-use cases before, but now I am planning to roll out a somewhat larger implementation with a dual cloud and dual hub, complicated by the fact that I don’t control the perimeter router at our DC and I […]
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The post Professional Loneliness appeared first on Packet Pushers Podcast and was written by Matthew Mengel.
Don’t Need No Stinking Underlays
Why’s everyone complaining about overlays; it’s the underlays that are the problem. I’ve been in this awful game for years, I’m tellin ya, me and the dinosaurs were buddies back in the medieval donkey days – so listen up losers, I’m diatribin from experience. That Greg Ferrous, he’s a wise fella; almost like a father to me […]
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The post Don’t Need No Stinking Underlays appeared first on Packet Pushers Podcast and was written by Steven Iveson.
Exploring OSPF Messages Between New Neighbors
A basic network is setup and OSPF is configured. R1 is then prevented from forming an OSPF adjacency with R2 due to R1’s serial interface being configured as a passive interface.
Only Hello packets are seen from R2.
From this Wireshark output we can see:
- OSPF Version 2 is utilized
- This is a Hello packet
- The Hello packet is sourced from a router with OSPF Router ID 2.2.2.2. Duplicate RIDs will prevent an OSPF adjacency and cause other issues.
- The interface that sourced this Hello packet resides in OSPF area 0. This item is used to verify that the two connected router interfaces are within the same OSPF area – this is a requirement in order to form an OSPF adjacency.
- No authentication is used
- A /30 network mask is used on R2’s connected interface. This item is used to verify that the two connected router interfaces are using the same subnet mask, which is a requirement in order to form an OSPF adjacency in addition to the two interfaces being within the same primary subnet.
- Hello and Dead timers. These must be the same on both connected routers in order to Continue reading
MrsJanitor’s Aus-Some Tour of SFO / SJC
Well I just got my itinerary for my trip to Sunnyvale for the Juniper Ambassador’s Summit in October and my wife and I have decided to spend an extra couple of days either side to get out and see the sites. We will be arriving in San Francisco at 11am Sat 5th of October and flying out around 11pm on Friday 12th, and we are looking to fill our schedule!
This is my wife’s first trip to the US, and I know she wants to get out and about and see things (also probably while Im in conference too). I know her list includes seeing the Golden Gate Bridge and Alcatraz… oh… and… “The Full House House”.
Thankfully we have the company of two of my good friends who are locals – Ashton (from Juniper) and my old work mate Cooper Lees, and we are working out “what we should see”.
So what do you consider “must see” things in this area? Let me know in the comments and we will see what we can fit in.
Also, while we’re in town, I would love to catch up with any locals in the area for drinks/coffee/food etc so Continue reading
The Priorities Bill of Rights – 10 practical steps to managing group priorities
Managers everywhere are abusing their employees by using priorities to convey to-do lists. It is not because of anything insidious in their objectives, but the average manager (both low- and high-level, by the way) simply doesn’t think enough about priorities to really do anything meaningful with them. For teams I lead, our entire existence revolves […]
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The post The Priorities Bill of Rights – 10 practical steps to managing group priorities appeared first on Packet Pushers Podcast and was written by Michael Bushong.