> -----Original Message----- > From: CentOS [mailto:centos-bounces at centos.org] On Behalf Of TE Dukes > Sent: Thursday, February 2, 2017 6:13 PM > To: 'CentOS mailing list' <centos at centos.org> > Subject: [CentOS] Spotty internet connection > > How do you IT guys diagnose the problem with a spotty internet connection? > > Just spent an hour on the phone with TWC/Spectrum. Of course they don't > see > anything wrong with their service. > > They send me to speedtest.net. The first attempt, the page didn't fully > load, the second attempt, the page didn't load at all, the third attempt, it > loaded. > > On a 20/2MB line I get 24.83/2.47MB. The speed is better than what I'm > paying for but its spotty. > > Lately I have been getting slow and partial page loads, server not found, > server timed out, etc.. Get knocked off ssh when accessing my home server > from work, etc. Its not the work connection because I don't have problems > accessing other sites, just here at home and my home server. > > Is there any kind of utility to check for failing hardware? All depends where and what the fault is. You can use wireshark to check for duplicate acknowledgements and retransmissions, that's low hanging fruit. Two recent issues I found that manifested in miserable browsing speed where poor dns resolution speed (many tools exist to determine your optimal forwarders or if you using the root hints it might expose this is a less than optimal configuration) made for long pauses and a bad cable for a user. The cable worked, and on the lan the retries made it seem like there wasn't problem. Over the wan, the retries made everything painfully slow.