Check Common Wifi Router Issues
Understanding Internet Addressing
When connecting to the Internet, you are assigned a unique Public IPv4 address like 30.147.234.239 or an IPv6 address like 2000:7cbb:60fb:4f5d:4caa:6ad7:f62a:dd48. A convenient way to check this is through https://test-ipv6.com/. However, communicating these addresses, or even MAC addresses like 53:a9:01:63:d9:4c, can be prone to errors and quickly become complex, especially for non-technical users. Moreover, it does not provide historical data, particularly for past issues.
Navigating the World Wide Web
Accessing a website such as https://stamm.info involves initially communicating with a DNS server to translate the host portion (stamm) combined with the Top Level Domain (info) of the URL, into an IP address like 188.190.189.121. In the process of sending web requests, your computer and browser relay 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).
Significance of Default Gateways
Typically obtained automatically through DHCP, your default gateway is essential for routing all of your computer’s traffic. You are assigned a default gateway like 192.168.144.185, often ending in .1 or .254 depending on the scope size. More information on how to fix IPv6 connectivity can be found in our in-depth discussion at how-to-fix-ipv6-connectivity/. Verification on Mac or Linux systems can be done through:
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 192.168.144.185 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 fe80:22f0:8fe4:609e:5696%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): {131.22.87.182, 142.53.36.151}
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 53:a9:01:63:d9:4c
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 06:0c:43:f7:57:6e
}
Resolving Issues with Wired or Wireless Connectivity
When transmitting data to your router, you may be using either a wired or a wireless (Wi-Fi) medium at the physical and data layer.
Troubleshooting Tips for Apple macOS / OSX Users
Regardless of which version of OSX/macOS you are using - whether it’s 10.15.6, 11.4.2, or 12.1.6 - there are various tools available for troubleshooting. However, these manual actions and scripts do not provide a series of correlated values over time. For this reason, automated remote troubleshooting is particularly valuable for teams that have adopted remote work and Work From Anywhere (WFA).
Effective Built-in Scripts for Troubleshooting
An extremely useful tool on OSX/macOS is the sudo wdutil info command, which provides a dump of current wireless settings in the CLI and can also be configured to generate specific troubleshooting logs. Furthermore, the sysdiagnose tool can be used to generate an extensive range of logs, although much of the information is only relevant to a specific point in time. To run it in the background and save logs to /var/tmp/<blah>.tar.gz, you can use the command sudo nohup /usr/bin/sysdiagnose -u &. If you prefer to run it interactively, you can use the command sudo /usr/bin/sysdiagnose, which will provide a privacy warning and open Finder in the correct location. It’s important to note that the file sizes can range from 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 🏠🏝🛰.
