How To Check Apple Internet
Understanding Internet Addressing
When using the Internet, you will be assigned a Public IPv4 address, such as 62.125.120.30, or an IPv6 address, such as 2000:9f01:2c8b:743:f7be:ac82:c9ae:3d4c. These addresses can be verified at https://test-ipv6.com/. However, attempting to convey these addresses to individuals who are not familiar with technology, or even mentioning MAC addresses like a9:1d:b1:91:bd:84, can be prone to errors and become complex quickly. Furthermore, this method does not provide any historical data, especially when past issues arise.
Navigating the World Wide Web
In order to access a website like https://barrows-schroeder.io, you first contact a DNS server to convert the host portion (barrows-schroeder) combined with the Top Level Domain (io) of the URL to an IP address, such as 207.57.131.247. When making web requests, your computer and browser actually transmit their type, for example: Mozilla/5.0 (Windows NT x.y; Win64; x64; rv:10.0) Gecko/20100101 Firefox/10.0
Understanding the Significance of Default Gateways
Your default gateway is typically an automatically configured address obtained via DHCP. A default gateway, such as 192.0.0.213 (usually ending in .1 or .254 depending on the scope size), is where your computer sends all of its traffic to be routed onward. For IPv6, a detailed guide on how-to-fix-ipv6-connectivity/ is available, but on Mac or Linux, you can perform a check 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 192.0.0.213 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 fe80:2e11:b634:6336:5719%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): {88.206.181.186, 41.216.234.60}
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 a9:1d:b1:91:bd:84
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 f2:d1:d1:ea:c6:f7
}
Resolve Issues with Wired and Wireless Networks
When it comes to sending data to your router, you may be utilizing either a wired or wireless (Wi-Fi) medium at the physical and data layer.
Actions to Take for Apple’s macOS / OSX
No matter which version of OSX/macOS you are operating on, whether it’s 10.14.3, 11.2.4, or 12.1.7, there are various tools available for addressing issues. However, these manual actions and scripts do not provide a set of correlated values over time. This is where the automated remote troubleshooting becomes essential, especially for teams that are adopting remote work and Work From Anywhere (WFA).
Utilize the In-Built Scripts
An extremely helpful tool on OSX/macOS is sudo wdutil info, which provides a dump of the current wireless settings to the CLI, and can be configured to generate specific troubleshooting logs as well. Moreover, the sysdiagnose tool can be used to generate a wide range of logs, although most of them are only relevant to wireless settings just like wdutil.
To run sudo nohup /usr/bin/sysdiagnose -u & in the background and have it write logs to /var/tmp/<blah>.tar.gz. Alternatively, you can run it interactively by using sudo /usr/bin/sysdiagnose, which will give a privacy warning. When it is 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 point Finder to the path. However, be cautious of the file sizes which are approximately 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 🏠🏝🛰.
