How Can I Test Common Wifi Internet Issues
Understanding the Functioning of Internet Addresses
When using the Internet, you are assigned a Public IPv4 address such as 87.32.234.50 or an IPv6 address like 2000:cee6:e024:5bfe:35c3:3d3a:32d3:c16a. It is possible to verify this information by visiting https://test-ipv6.com/. Nevertheless, for individuals who are not well-versed in technology, communicating these addresses or MAC addresses like ad:e5:ef:c1:e7:84 can lead to errors and complications. Furthermore, this method does not provide any historical data, particularly when addressing previous issues.
Navigating the Internet
In order to access a website like https://huel-jenkins.io, you first connect to a DNS server to translate the host (huel-jenkins) and the Top Level Domain (io) of the URL into an IP address, such as 18.83.190.178. Your computer and browser transmit their types with every web request, as shown: Mozilla/5.0 (Windows; U; Win 9x 4.90; SG; rv:1.9.2.4) Gecko/20101104 Netscape/9.1.0285
The Significance of Preset Gateways
The default gateway is usually an automatically assigned address through DHCP. Typically, your computer obtains a default gateway like 10.161.106.69 (often ending in .1 or .254 based on the scope size), which serves as the point where all your computer’s traffic is forwarded. For IPv6, detailed instructions can be found in our blog post how-to-fix-ipv6-connectivity/, but it can also be checked on Mac or Linux using the following command:
IPv4 Routes and the Host IPv4 Route Table (inc. VPN)
netstat -rn -f inet | egrep -i "default|0/1|128.0/1"
0/1 172.18.12.193 UGScg utun3 default 10.161.106.69 UGScg en0 128.0/1 172.18.12.193 UGSc utun3
Note: We are not just looking for the default but also for any VPN that overrides the public v4 address space.
IPv6 Routes and the Host IPv6 Route Table (inc. VPN)
netstat -rn -f inet6 | egrep -i "default|2000::/3"
If you have IPv6 active the above should return at least one route (as per below) via a known interface such as “en0 " on a Mac.
default fe80:efb4:7a77:438f:68d1%en0 UGcg en0 default fe80::%utun0 UGcIg utun0 default fe80::%utun1 UGcIg utun1 default fe80::%utun2 UGcIg utun2 2000::/3 utun3 USc utun3
Note: We are not just looking for the default but also for any VPN that overrides the public v6 address space.
Debugging DHCP for both IPv4 and IPv6
To get a look at the low level DHCP configuration (Mac/Linux):
ipconfig getpacket en0
...
domain_name_server (ip_mult): {127.132.13.236, 218.163.250.160}
end (none):
...
So, in the above we are not getting IPv6 DNS servers from the DHCPv4 reply but…
ipconfig getv6packet en0
DHCPv6 REPLY (7) Transaction ID 0x80940b Length 76
Options[4] = {
CLIENTID (1) Length 14: DUID LLT HW 1 Time 668691856 Addr ad:e5:ef:c1:e7:84
DNS_SERVERS (23) Length 32: 2606:4700:4700::1111, 2001:4860:4860::8844
DOMAIN_LIST (24) Length 0: Invalid
SERVERID (2) Length 10: DUID LL HW 1 Addr f7:81:7d:ae:b0:ae
}
Resolve Connectivity Issues for Wired and Wireless Networks
When transmitting data to your router, you may encounter issues at the physical and data layer, whether you are using a wired or wireless (Wi-Fi) medium.
Strategies for Addressing Connectivity Problems on Apple macOS / OSX
Regardless of the version of OSX/macOS you are using, whether it’s 10.13.7, 11.3.7, or 12.3.7, there are various methods for troubleshooting. However, these manual processes and scripts do not provide a set of interconnected values over time. This is where automated remote troubleshooting becomes invaluable, particularly for teams that have embraced remote work and the concept of Work From Anywhere (WFA).
Leveraging Built-in Scripts for Assistance
An extremely useful tool on OSX/macOS is the sudo wdutil info command, which provides a dump of the current wireless settings to the command-line interface, and can also be configured to generate specific logs for troubleshooting. Additionally, the sysdiagnose tool offers a more comprehensive option for generating a wide range of logs (although many are only relevant to wireless at a specific moment, similar to wdutil).
To run sysdiagnose in the background and write the logs to /var/tmp/<blah>.tar.gz, use the command sudo nohup /usr/bin/sysdiagnose -u &. For interactive execution (although there is minimal interaction), use the command sudo /usr/bin/sysdiagnose and be prepared to encounter a privacy warning. When not run in the background, it should open Finder in the appropriate location, or you can navigate to /var/tmp either manually or by using the path-finding shortcut in Finder with Cmd+Shift+G. Keep in mind that the file sizes will be approximately 300MB or slightly more.
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Digital work requires reliable connectivity. Whether for low latency or regular data streams, Wi-Fi, DNS, and network issues cause teams to lose time and productivity. Even worse is when support teams waste time trying to recreate and isolate issues! See how PanSift saves time, money, and frustration on all sides with instant remote troubleshooting 🏠🏝🛰.
