Category: network management
Supposedly it was a problem with the management network used by their optical gear, but it looks a lot like a layer-2 network spanning 15 data centers and no control-plane policing on the managed devices… proving yet again that large-scale layer-2 networks are a really bad idea.
I asked David Gee to review my streaming telemetry blog posts to make sure I didn’t make too many blunders, and he sent me a nice summary of his view on the topic in return.
The only thing I could do after reading it was to ask him for permission to do a copy-paste. Here it is:
Continuing the Streaming Telemetry saga, let’s focus on presentation formats and transport mechanisms.
I already mentioned three presentation formats: XML (used by NETCONF), JSON (used by RESTCONF) and Protocol Buffers (used by gRPC). Two of them are text-based, the third one (Protocol Buffers) is binary encoding not unlike ASN.1 BER used by SNMP. That can’t be good in a JSON-hyped world, right?
During the Campus Evolution with Cat9K presentation (I hope I got it right - the whole event was an absolute overload) the presenter mentioned the benefits of brand-new model-driven telemetry, which immediately caused me to put my academic hat on and state that we had model-driven telemetry for at least 30 years.
Don’t believe me? Have you ever looked at an SNMP MIB description? Did it look like random prose to you or did it seem to have some internal structure?
I don’t think I’ve ever been at a Tech Field Day event that’s been as intense as what we went through in the last few days at Cisco Live Europe – at least 17 different presentations in two days. It’s still all a blur and will take a long while to sort out.
One of the more interesting presentations we had during Tech Field Day Extra @ Cisco Live Berlin was coming from Paessler, a company developing PRTG, a little-known network monitoring software.
Monitoring SDN Networks is the featured webinar of June 2017, and in the featured video Terry Slattery (CCIE#1026) talks about network analysis of SDN.
If you’re a trial subscriber, log into my.ipspace.net, select the webinar from the first page, and watch the video marked with star… and if you’d like to try the ipSpace.net subscription register here.
One of the challenges of designing a controller-based solution is the transport network used to exchange information between controller and controlled devices. Can you do that in-band or is it better to have an out-of-band network (built with traditional components)? Terry Slattery explained some of the pros and cons in the Monitoring SDN Networks webinar.
In Episode 69 of Software Gone Wild we discussed ways of increasing visibility into VXLAN transport fabric. Another thing we badly need is visibility into the virtual edge behavior, and to help you get there Iwan Rahabok created a set of vRealize dashboards that include the virtual edge networking components. Hope you’ll find them useful.
If you're a networking engineer, sysadmin, or NetDevOps guru preferring the power of CLI over carpal-syndrome-inducing GUI you might like the My Looking Glass tool developed by Mehrdad Arshad Rad. Haven't tried it out, but the intro on GitHub page looks promising.
If you decide to try it out (or already did) please share your experience in a comment. Thank you!
When people started talking about OpenConfig YANG data models, my first thought (being a grumpy old XML/XSLT developer) was “that should be really easy to implement for someone with XML-based software and built-in XSLT support” (read: Junos with SLAX).
Here’s how my simplistic implementation would look like:
My friend Jeremy Stretch wrote an IPAM+DCIM tool for Digital Ocean and open-sourced it. As the tool was designed by networking engineers to manage data center networks (more in Jeremy’s blog post), it might be a better fit than other tools out there. In any case, check it out and let me know how it works.
After listening to Open-Source Network Engineer Toolbox Nick Buraglio sent me an email saying “we should do another podcast on open-source network management tools…” and so we did. In Episode 56 of Software Gone Wild Nick, Elisa Jasinska and myself discussed a whole range of network management challenges and open-source tools you can use to address them.
Imagine you’d design your network by documenting the desired traffic flow across the network under all failure conditions, and only then do a low-level design, create configurations, and deploy the network… while being able to use the desired traffic flows as a testing tool to verify that the network still behaves as expected, both in a test lab as well as in the live network.
Time for another fill-in-the-blanks survey: how many vendors support NETCONF and/or REST API in their data center switches, routers, firewalls and load balancers?
Please help me complete the tables by writing a comment – and do keep in mind that it only counts if it’s documented in a public configuration guide on vendor’s web site.
Also, I’m not aware of any vendor using standard NETMOD YANG models. If someone does, please let me know.