How Do You Check Mac Internet Connection
Understanding Internet Addressing
The addressing system of the Internet involves having a Public IPv4 address such as 170.244.135.51 or an IPv6 address such as 2000:e9ff:eb5b:ad2a:ce2d:779f:6:1c58. These can be checked using https://test-ipv6.com/. Communicating these addresses to non-technical individuals or referring to MAC addresses like 74:c9:47:2f:a1:ba can become complex and prone to errors. Also, it lacks historical data, especially for past issues.
Navigating the World Wide Web
Accessing a website like https://hilpert.biz involves initially accessing a DNS server to convert the host portion (hilpert) combined with the Top Level Domain (biz) of the URL to an IP address such as 73.180.234.251. Every web request sent by your computer and browser includes its type, for example: Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; AS; rv:11.0) like Gecko
Significance of Default Gateways
The default gateway is typically an address automatically configured via DHCP. It is usually in the form of 192.168.68.188 (although they typically end in .1 or .254 depending on the scope size) and serves as the routing point for all outgoing computer traffic. For IPv6, more detailed information can be found at how-to-fix-ipv6-connectivity/, while on Mac or Linux systems, it can be verified 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 192.168.68.188 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 fe80:30ab:fc4e:9125:fab0%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): {94.22.216.202, 233.89.147.233}
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 74:c9:47:2f:a1:ba
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 2d:ae:15:21:f0:8d
}
Fixing Issues with Wired and Wireless Connection
When it comes to transmitting data to your router, you might be using a wired or wireless (Wi-Fi) connection at the physical and data layer.
Tips for Troubleshooting on Apple macOS / OSX
Regardless of whether you are running OSX/macOS versions like 10.13.3, 11.3.4, or 12.1.7, there are various tools available for troubleshooting. However, these manual actions and scripts do not provide a set of interconnected values over time. This is where automated remote troubleshooting becomes valuable, particularly for teams that are transitioning to remote work and embracing the Work From Anywhere (WFA) model.
Useful Built-in Scripts
One useful tool on OSX/macOS is the sudo wdutil info command, which provides a dump of current wireless settings to the command line interface and can also be configured to generate specific logs for troubleshooting. In addition, the sysdiagnose tool can be used to produce a wide range of logs, although much of it is only relevant to wireless settings at a specific point in time, similar to wdutil.
To run it in the background and generate logs in /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 sudo /usr/bin/sysdiagnose but be prepared for file sizes of approximately 300MB. You can find the logs in the correct location in Finder, navigate to /var/tmp, or use Cmd+Shift+G to point Finder to the path. Be mindful of the file sizes, which can vary around 300MB.
Possibly Helpful Videos
P.S. Tips For Remote Network and Client Support
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 🏠🏝🛰.
