Help Diagnosing Ongoing Network Issues

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FlanZarianick
Posts: 8
Joined: Sun Jun 26, 2022 7:28 am

Help Diagnosing Ongoing Network Issues

Post by FlanZarianick »

Lately I have been having network and other odd slowdowns. What collection tools can I get installed to see what the problem is? I can't tell if it is DNS, QoS, bad router, or other issues.

A bit about my network:

TWC Roadrunner cable to a Motorola Surfboard 6141

Ooma Telo (I tried connecting the router first and there were VoIP dropouts and bad quality when it wasn't dropped, so I moved it back to direct connect to modem)

Netgear WNDR4500 (N900) providing routing and WiFi

Wired directly to the WNDR4500 are my home media devices: PS3, Roku, TiVo

Upstairs office is connected to WNDR4500 via DLink 500 Powerline adapter. That is where my NAS and Plex servers are, providing media for the whole house. Plex is a VMware Fusion VM and there is plenty of host resources available to set up a Linux VM or VMware appliance for monitoring up there.

Plex and DLNA streaming appear to be perfectly fine, as does Netflix, et al. from Roku and PS3.

WiFi (iOS or Mac) can be slow or stopped at times. Never disconnected, though. Wired can feel like it's slow, but far less often and I don't know if it is just me thinking it is slow. (Where "slow" can be either responsiveness/latency or throughput)

I tried swapping out DNS servers with Google and OpenDNS with no appreciable improvement.

What can I do/install on the network to see what the problem is? I tried Nagios and it needs SNMP, which the Netgear does not provide. Is there some set of Windows or Linux utilities I can constantly run to see packet drops vs. DNS requests vs. hardware downtime? I can do this with enterprise tools, but not with consumer level hardware.

I have some DD-WRT-able Linksys routers if that helps, but they are not 802.11n.

I hope I'm not trying to kill a fly with a sledgehammer.
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swolf
Developer
Posts: 294
Joined: Tue Jun 06, 2017 9:48 am

Re: Help Diagnosing Ongoing Network Issues

Post by swolf »

Hi @FlanZarianick, thanks for reaching out.

I'm going to move this to the Nagios XI section, since you seem to be asking about a general monitoring question.

I think Nagios XI can check for a lot of these things separately, if you know what you want to check - if you're looking to measure packet loss, for instance, you can measure that with a ping check. ICMP traffic tends to be lower priority on most routers, so those packets are the most likely to get dropped. In general, though, you're going to be reduced to monitoring the path from your monitoring server to somewhere else.

I will also say that if your router doesn't have SNMP, it's probably a consumer-grade device that isn't intended to be monitored. If you're trying to get measurements for all traffic on the device, and not just traffic from specific devices, your best bet is to get a device that supports that. You may be able to work around this, but I wouldn't expect it to be 1-2 hours of researching and fixing, it's more likely to be something where you could have more efficiently bought the device with better capabilities.
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