Over the years I have been able to narrow the most common reasons a service provider goes down or has an outage. This is, by no means, an extensive list. Let’s jump in. Layer1 outages Physical layer outages are the easiest and where you should always start. If you have had any kind of formal training you have ran across the OSI model. Fiber cuts, equipment failure, and power are all physical layer issues. I have seen too many engineers spend time looking...
Continue reading...troubleshooting
LibreNMS syslog.ibd cleanup
Recently I ran into an issue where a librenms install was taking up a crazy amount of disk space. This was tracked down to the syslog.ibd file . Even thought I had set my options to be less than 10 days per this link https://docs.librenms.org/Support/Cleanup-options/ I still was having a huge file. Here is what I did to fix it. My root partition was too full to start MariaDB. I went into var and cleaned out enough log files to make space to...
Continue reading...Network troubleshooting tools
Recently, there was a thread on the NANOG list asking what were somne favorite network troubleshooting tools. I have taken many of these tools and created the following list. http://ping.pe/Simple pingport and dig commands https://mtr.sh/BGP Looking glass https://perfops.net/mtr-from-worldTraceroute from various hosts on the net http://www.traceroute6.net/IPV6 tools (ping,traceroute,etc) https://dnsviz.net/Carious DNS tools http://irrexplorer.nlnog.net/Routing Registry object explorer https://mxtoolbox.com/DNS and Mail tools
Continue reading...Frequently Asked Questions On OTDRS
https://www.thefoa.org/tech/ref/testing/OTDR/OTDR-FAQS.html?fbclid=IwAR1wWEr5qG0h4r2vBsnEEmCWrT20VYIWGCnseOD2_MChJiaL6PX9RaCm1ow Frequently Asked Questions On OTDRS And Hints On Their Use OTDRs, also known by their technical name optical time domain reflectometers, are valuable fiber optic testers when used properly, but improper use can be misleading and, in our experience, lead to expensive mistakes for the contractor. We have been personally involved in several instances where misapplication of OTDR testing has cost the contractor as much as $100,000 in wasted time and materials. Needless to say, it’s extremely important to understand how to...
Continue reading...A little reboot now and then..
Just a reminder that rebooting does help. My home network was experiencing slowness and lag
Continue reading...MTR Traceroute and you
MTR is a visual application that combines the functionality of the traceroute and ping in a single network diagnostic tool.
Continue reading...Troubleshooting a fiber optic link on Cisco switches
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Continue reading...Podcast: Quick troubleshooting for ISP networks
Podcast: Play in new window | Download (Duration: 7:22 — 10.3MB)
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Troubleshooting for ISP networks. Quick podcast on using layers 1-3 for making your admin life easier.
Continue reading...11 Reasons your Internet is slow
If your video is lagging and downloads are taking forever, don’t bang your head on your keyboard. Try these fixes
Continue reading...Down detection for Netflix, Hulu, etc.
Are you an ISP and need to check if it’s you or Netflix? Maybe your gamers are calling and can’t log in to Apex legends? Check out https://downdetector.com/
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