How Do You Test Apple Internet

Understanding Internet Addressing

When using the internet, an individual may be assigned a Public IPv4 address like 170.20.81.26 or an IPv6 address like 2000:d56d:2612:20d4:1272:59:a8f7:f3a7. These addresses can be verified at https://test-ipv6.com/. However, conveying these addresses to those who are not tech-savvy, or even referencing MAC addresses like 6a:67:48:8a:b4:70, can be prone to errors and become complex. Furthermore, historical data is not provided, particularly related to previous issues.

Navigating the World Wide Web

When attempting to access a website such as https://ernser-ferry.info, the process begins with a request to a DNS server in order to convert the host name (ernser-ferry) combined with the Top Level Domain (info) of the URL into an IP address, such as 148.195.74.191. Interestingly, all web requests from a computer and browser include a type, for example
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

The default gateway is typically an automatically assigned address through DHCP, such as 192.0.0.59 (usually ending in .1 or .254 depending on the scope size). This is where a computer forwards all of its traffic to be routed. For IPv6, detailed instructions are available in our blog post how-to-fix-ipv6-connectivity/. On Mac or Linux, it’s possible to verify this 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  192.0.0.59    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:e877:7e25:e78d:2e63%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): {253.189.124.33, 96.235.7.57}
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 6a:67:48:8a:b4:70
  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 0b:49:ae:0b:16:2b
}

Resolving Issues with Wired and Wireless Connections

When it comes to sending data to your router, you might be utilizing a wired or wireless (Wi-Fi) medium at the physical and data layer.

Tips for Apple macOS / OSX Troubleshooting

Regardless of whether you are using OSX or macOS version 10.14.3, 11.3.5, or 12.3.3, there are various troubleshooting tools available. However, these manual actions and scripts do not provide a set of correlated values over time. This is where automated remote troubleshooting becomes essential, particularly for teams that are embracing remote work and Work From Anywhere (WFA).

Utilizing Pre-installed Scripts for Assistance

A useful tool for OSX/macOS is sudo wdutil info, which provides a dump to the CLI of current wireless related settings and can be configured to generate specific logs for troubleshooting. Furthermore, the sysdiagnose tool can be used to generate a wide range of logs, although much of it is only relevant to wireless at a particular point in time, similar to wdutil.

By running sudo nohup /usr/bin/sysdiagnose -u &, it will run in the background and write logs to /var/tmp/<blah>.tar.gz for you. If you prefer to run it interactively (even though there is not much interaction), you can use
sudo /usr/bin/sysdiagnose and it will give 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 use Finder with Cmd+Shift+G to navigate to the path. Keep in mind that the file sizes are approximately 300MB more or less.

Possibly Helpful Videos

Video	Title	Channel
	Spotlight on Spotlight - Hands-On Mac 7	Hands-On Mac
	Secret Mac Boot Commands - Mac Boot Key Combinations	Hands-On Mac
	macOS Big Sur - What's New in Apple macOS 11	Hands-On Mac
	On the Road to Big Sur 2 - Compatibility	Hands-On Mac
	Mac Activity Monitor - How to Troubleshoot Your Mac	Hands-On Mac

Table 1.0 - Video Help