How Do You Support Common Wifi Issues
Understanding Internet Protocol Addressing
When utilizing the Internet, you may be assigned a Public IPv4 address such as 181.0.137.224 or an IPv6 address like 2000:a822:21d5:8c86:38a9:fcd0:a34:7908. A simple way to verify this is by visiting the site https://test-ipv6.com/. However, relaying these addresses to those less experienced in technology, or even referencing MAC addresses like 3f:8d:b5:c9:f2:13, can be prone to mistakes and quickly becomes complex. Furthermore, this method does not provide any historical data, particularly from past occurrences.
Navigating the World Wide Web
Accessing a website such as https://halvorson.com initially involves contacting a DNS server to translate the host aspect (halvorson) combined with the Top Level Domain (com) of the URL to an IP address, such as 228.82.47.39. Interestingly, upon sending web requests, your computer and browser also convey their type, for instance: Mozilla/5.0 (compatible; MSIE 9.0; AOL 9.7; AOLBuild 4343.19; Windows NT 6.1; WOW64; Trident/5.0; FunWebProducts)
The Significance of Default Gateways
Typically configured automatically by DHCP, your default gateway is assigned an address like 172.29.152.26 (although they generally conclude with .1 or .254 based on the scope size). This is the location where your computer directs all of its traffic to be routed. If you wish to delve deeper into the topic with regards to IPv6, you can refer to our detailed guide on how-to-fix-ipv6-connectivity/. Alternatively, you can verify this 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 172.29.152.26 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 fe80:6a4c:11ac:2b93:3fc0%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): {15.188.218.4, 9.5.246.56}
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 3f:8d:b5:c9:f2:13
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 07:16:46:c8:23:14
}
Solutions for Wired and Wireless Connectivity Issues
When it comes to transmitting data to your router, you may encounter connectivity issues at the physical and data layer, whether you are using a wired or wireless (Wi-Fi) medium.
Troubleshooting Tips for Apple macOS / OSX Users
Regardless of which version of OSX/macOS you are using, whether it’s 10.14.4, 11.2.8, or 12.2.8, there are various tools available for troubleshooting. However, these manual methods and scripts do not provide a series of correlated values over time. This is where the need for automated remote troubleshooting arises, particularly for teams that are adapting to remote work and embracing the concept of Work From Anywhere (WFA).
Useful Built-in Scripts
One of the useful tools on OSX/macOS is the sudo wdutil info, which provides a dump of current wireless settings to the CLI and can also be configured to generate specific logs for troubleshooting. Additionally, the sysdiagnose tool can be used to generate a wide range of logs, although most of the information is only point-in-time in relation to wireless, similar to wdutil.
To run it in the background and write logs to /var/tmp/<blah>.tar.gz, use the command sudo nohup /usr/bin/sysdiagnose -u &. If you prefer to run it interactively, use sudo /usr/bin/sysdiagnose, but be aware that it will give a privacy warning. The file sizes are approximately 300MB, so keep that in mind.
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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 🏠🏝🛰.
