Check Common Wifi Internet Issues
Understanding the Functionality of Internet Addressing
When using the Internet, it is common to have a Public IPv4 address, such as 5.181.6.26, or an IPv6 address, like 2000:ce70:7959:5705:92a0:2900:42ae:4270. These can be verified by visiting https://test-ipv6.com/. However, relaying these addresses to individuals who are not technologically inclined or even mentioning MAC addresses, like c1:d6:35:0d:0f:79, can become complicated and prone to errors. Furthermore, historical data is not accessible, especially concerning past issues.
Navigating the World Wide Web
Accessing a web page, such as https://lebsack.name, initially requires querying a DNS server to convert the host portion (lebsack) combined with the Top Level Domain (name) of the URL into an IP address, like 26.253.167.206. When making web requests, your computer and browser disclose the type of the request, for example Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36.
Understanding the Significance of Default Gateways
The default gateway is typically an address that is automatically configured via DHCP. When utilizing DHCP, you will receive a default gateway, such as 192.0.0.46 (though, they usually end in .1 or .254 based on the scope size), where all of your computer’s traffic is routed. For a detailed analysis of IPv6, you can refer to how-to-fix-ipv6-connectivity/ or inspect on Mac or Linux with:
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 192.0.0.46 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:e768:1ccd:7925:b7b9%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): {164.181.140.43, 181.68.183.249}
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 c1:d6:35:0d:0f:79
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 ab:20:0e:40:f8:15
}
Solve Problems with Wired and Wireless Connections
When it comes to transmitting data to your router, you might be using a wired or wireless (Wi-Fi) medium at the physical and data layer.
Troubleshooting Tips for Apple macOS / OSX Users
No matter which version of OSX/macOS you’re using - whether it’s 10.11.9, 11.4.5, or 12.0.7 - there are various tools available for troubleshooting. However, these manual actions and scripts don’t provide a set of correlated values over time. This is where automated remote troubleshooting comes into play, especially for teams that are embracing remote work and the Work From Anywhere (WFA) concept.
Utilizing Built-in Scripts for Assistance
A very useful tool on OSX/macOS is the sudo wdutil info command, which provides a dump to the CLI of current wireless-related settings and can be configured to generate specific logs for troubleshooting. Moreover, the sysdiagnose tool can be used to generate a wide range of logs, although much of it is only relevant to wireless at a single point in time, similar to wdutil.
Running sudo nohup /usr/bin/sysdiagnose -u & in the background will write logs to /var/tmp/<blah>.tar.gz for you. If you prefer to run it interactively, you can execute sudo /usr/bin/sysdiagnose, which will then give a privacy warning. When not run in the background, it should open Finder in the correct location, or you can navigate to /var/tmp or use Finder with Cmd+Shift+G to point Finder to the path. Be cautious of the file sizes, as they are typically around 300MB.
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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 🏠🏝🛰.
