Support Wifi Issues
Understanding Internet Addressing
When using the Internet, you are assigned a Public IPv4 address such as 75.99.209.215 or an IPv6 address like 2000:b4ae:62be:47fb:88f0:d518:7d64:dd42. A quick way to check this is through https://test-ipv6.com/. However, conveying these addresses, or even mentioning MAC addresses like 3a:bb:d9:ff:49:34, can be error-prone and complex for those not well-versed in technology. Furthermore, this does not provide any historical data, especially regarding past issues.
Navigating the Internet
Accessing a webpage like https://yost.biz involves an initial connection to a DNS server in order to translate the host portion (yost) and the Top Level Domain (biz) of the URL into an IP address like 142.32.29.227. Your computer and browser also include its type in all web requests, such as Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36
The Significance of Default Gateways
Your default gateway is typically automatically configured through DHCP and comes in the form of an address like 192.0.0.108 (although they typically end in .1 or .254, depending on the scope size). This is where your computer sends all its traffic to be routed onwards. For IPv6, you can find a comprehensive guide on how-to-fix-ipv6-connectivity/, or check 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 192.0.0.108 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:f9a6:9a94:84a1:4de1%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): {68.140.232.23, 28.101.153.243}
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 3a:bb:d9:ff:49:34
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 8a:64:2c:b1:1c:2f
}
Solutions for Wired and Wireless Network Issues
When it comes to transmitting data to your router, you may encounter issues with both wired and wireless (Wi-Fi) connections at the physical and data layer.
Troubleshooting on Apple macOS / OSX
Regardless of whether you are using OSX, macOS 10.12.6, 11.6.4, or 12.0.9, there are several troubleshooting tools available. While manual actions and scripts can be helpful, they do not provide a comprehensive set of correlated values over time. This is where automated remote troubleshooting becomes essential, especially for teams that support remote work and Work From Anywhere (WFA).
Useful Built-in Scripts
One valuable tool on OSX/macOS is the sudo wdutil info command, which provides a dump of the current wireless settings to the CLI and can also generate specific logs for troubleshooting. For a more comprehensive set of logs, the sysdiagnose tool can be used to generate a wide range of logs related to wireless issues, albeit many of them are only relevant to a specific 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 use the command sudo /usr/bin/sysdiagnose, which will prompt a privacy warning. When not run in the background, it should open Finder in the correct location, or you can navigate to /var/tmp using Finder with Cmd+Shift+G. Keep in mind that the file sizes will be roughly 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 🏠🏝🛰.
