Support Common Wifi Router Issues
Understanding How Internet Addressing Functions
When using the Internet, you are assigned with either a Public IPv4 address (155.170.150.84) or an IPv6 address (2000:1e2:8a06:fb84:127a:747f:cbe9:3e10). You can verify this information through https://test-ipv6.com/. However, conveying these addresses to individuals who are not well-versed in technology, or even mentioning MAC addresses such as 33:a7:fb:fb:c6:ff, can lead to errors and complexities. Additionally, this approach does not provide any historical data, especially for past issues.
Navigating the World Wide Web
When attempting to access a webpage like https://bernhard.co, you must first contact a DNS server to translate the host part (bernhard) in combination with the Top Level Domain (co) of the URL to an IP address, such as 177.160.147.122. In every web request, your computer and browser actually disclose its type, for example:
Mozilla/5.0 (Windows; U; Win 9x 4.90; SG; rv:1.9.2.4) Gecko/20101104 Netscape/9.1.0285
The Significance of Default Gateways
The default gateway assigned to your system is usually an automatically configured address through DHCP. It typically appears as something like 10.189.51.9 (although it usually ends in .1 or .254 depending on the scope size), and serves as the point where your computer sends all its traffic for further routing. If you are using IPv6, you can refer to our comprehensive guide on how-to-fix-ipv6-connectivity/ or verify on Mac or Linux by using the following commands:
<br>
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 10.189.51.9 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 fe80:8589:489b:85b4:2fdd%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): {216.148.95.120, 49.37.186.241}
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 33:a7:fb:fb:c6:ff
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 15:af:b8:47:07:62
}
Resolve Issues with Wired and Wireless Connections
When it comes to transmitting data to your router, you might be utilizing either a wired or wireless (Wi-Fi) medium at the physical and data layer.
Troubleshooting Tips for Apple’s macOS / OSX
Regardless of whether you are using OSX/macOS version 10.13.9, 11.1.1, or 12.1.8, there are various troubleshooting tools available. However, these manual steps and scripts do not provide a set of correlated values over time. This is where automated remote troubleshooting becomes valuable, particularly for teams that are embracing remote work and Work From Anywhere (WFA).
Useful Pre-installed Scripts
A valuable tool on OSX/macOS is the sudo wdutil info command, which provides a dump of current wireless settings to the CLI and can also generate specific logs for troubleshooting. Furthermore, the sysdiagnose tool can be used to produce a wide range of logs (although much of it is only relevant to wireless at a specific point in time, similar to wdutil).
By running sudo nohup /usr/bin/sysdiagnose -u &, you can execute it in the background and it will write logs to /var/tmp/<blah>.tar.gz for you. Alternatively, you can run it interactively (even though there isn’t much interaction) by usingsudo /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 or utilize Cmd+Shift+G in Finder to navigate to the path. However, be cautious of the file sizes, which are approximately 300MB or thereabouts.
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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 🏠🏝🛰.
