4 ms·

This has been standard Mac OS X behavior for a long time: on a machine with multiple IP addresses, connections will use the default gateway associated with the

This has been standard Mac OS X behavior for a long time: on a machine with multiple IP addresses, connections will use the default gateway associated with the interface providing that address.

monadic2 7y ago
Nobody claimed the OS was designed to be secure!
- geofft 7y ago
  https://www.apple.com/ipad/why-ipad/ https://www.apple.com/ipad/why-ipad/ Giant letters: "It's designed to be secure. And to protect your privacy."
  - monadic2 7y ago
    Welp, clearly a lie.
dahfizz 7y ago
As a Linux admin, I am thoroughly confused. Are you saying that MacOS maintains a separate routing table for each interface? Typically, a system has only one default route. You can have many interfaces and many routes, but only one default. Otherwise you don't know which default gateway to send a packet to.
- djrogers 7y ago
  The GP is wrong, and your understanding is correct - there is one routing table.
  - icehawk 7y ago
    There is one routing table but it can have multiple default gateways: fenrir:~ $ uname -a Darwin fenrir 18.7.0 Darwin Kernel Version 18.7.0: Tue Aug 20 16:57:14 PDT 2019; root:xnu-4903.271.2~2/RELEASE_X86_64 x86_64 fenrir:~ $ netstat -rn |head Routing tables Internet: Destination Gateway Flags Refs Use Netif Expire default 172.16.22.254 UGSc 85 732 en0 default 192.168.88.1 UGScI 2 49 en2 127 127.0.0.1 UCS 0 0 lo0 127.0.0.1 127.0.0.1 UH 1 3806 lo0 169.254 link#6 UCS 2 0 en0 ! 169.254 link#8 UCSI 0 0 en2 ! If you bind to a specific interface it will use that default gateway: fenrir:~ $ traceroute -ni en0 google.com traceroute to google.com (216.58.194.142), 64 hops max, 52 byte packets 1 172.16.22.254 0.565 ms 0.340 ms 0.300 ms 2 172.16.25.60 0.893 ms 0.727 ms 0.721 ms 3 172.16.25.0 0.954 ms 0.819 ms 0.815 ms 4 108.218.244.1 7.422 ms 1.908 ms 3.617 ms 5 *^C fenrir:~ $ traceroute -ni en2 google.com traceroute to google.com (216.58.194.142), 64 hops max, 52 byte packets 1 192.168.88.1 12.399 ms 3.768 ms 0.811 ms 2 192.168.80.1 1.950 ms 8.322 ms 1.702 ms 3 172.26.96.161 30.448 ms 393.449 ms 46.537 ms 4 107.72.199.60 182.826 ms 107.72.199.36 34.835 ms 107.72.199.60 50.557 ms 5 12.83.186.101 52.178 ms 32.536 ms 33.431 ms 6 12.83.186.85 38.516 ms 51.138 ms 61.687 ms 7 12.122.5.190 48.626 ms 251.733 ms 38.487 ms 8 12.122.2.197 58.184 ms 82.183 ms^C You can also also do this do this by IP address fenrir:~ $ traceroute -ns 192.168.88.243 google.com traceroute to google.com (216.58.194.142) from 192.168.88.243, 64 hops max, 52 byte packets 1 192.168.88.1 4.658 ms 10.498 ms 3.633 ms 2 192.168.80.1 4.264 ms 58.660 ms 7.153 ms 3 172.26.96.161 105.557 ms 41.207 ms 32.243 ms 4 107.72.199.60 66.562 ms Which interface is used when IP address / interface is not specified is selected by the Service Order setting in the Network control panel.
    - lathiat 7y ago
      You can actually do this on linux pretty easily but it's not the default, it's sometimes called "source routing" Easy to setup with netplan and systemd-networkd, a little more complex to do manually.

This has been standard Mac OS X behavior for a long time: on a machine with multiple IP addresses, connections will use the default gateway associated with the interface providing that address.

monadic2 7y ago

Nobody claimed the OS was designed to be secure!

geofft 7y ago
https://www.apple.com/ipad/why-ipad/ https://www.apple.com/ipad/why-ipad/ Giant letters: "It's designed to be secure. And to protect your privacy."
- monadic2 7y ago
  Welp, clearly a lie.

dahfizz 7y ago

As a Linux admin, I am thoroughly confused. Are you saying that MacOS maintains a separate routing table for each interface? Typically, a system has only one default route. You can have many interfaces and many routes, but only one default. Otherwise you don't know which default gateway to send a packet to.

djrogers 7y ago
The GP is wrong, and your understanding is correct - there is one routing table.
- icehawk 7y ago
  There is one routing table but it can have multiple default gateways: fenrir:~ $ uname -a Darwin fenrir 18.7.0 Darwin Kernel Version 18.7.0: Tue Aug 20 16:57:14 PDT 2019; root:xnu-4903.271.2~2/RELEASE_X86_64 x86_64 fenrir:~ $ netstat -rn |head Routing tables Internet: Destination Gateway Flags Refs Use Netif Expire default 172.16.22.254 UGSc 85 732 en0 default 192.168.88.1 UGScI 2 49 en2 127 127.0.0.1 UCS 0 0 lo0 127.0.0.1 127.0.0.1 UH 1 3806 lo0 169.254 link#6 UCS 2 0 en0 ! 169.254 link#8 UCSI 0 0 en2 ! If you bind to a specific interface it will use that default gateway: fenrir:~ $ traceroute -ni en0 google.com traceroute to google.com (216.58.194.142), 64 hops max, 52 byte packets 1 172.16.22.254 0.565 ms 0.340 ms 0.300 ms 2 172.16.25.60 0.893 ms 0.727 ms 0.721 ms 3 172.16.25.0 0.954 ms 0.819 ms 0.815 ms 4 108.218.244.1 7.422 ms 1.908 ms 3.617 ms 5 *^C fenrir:~ $ traceroute -ni en2 google.com traceroute to google.com (216.58.194.142), 64 hops max, 52 byte packets 1 192.168.88.1 12.399 ms 3.768 ms 0.811 ms 2 192.168.80.1 1.950 ms 8.322 ms 1.702 ms 3 172.26.96.161 30.448 ms 393.449 ms 46.537 ms 4 107.72.199.60 182.826 ms 107.72.199.36 34.835 ms 107.72.199.60 50.557 ms 5 12.83.186.101 52.178 ms 32.536 ms 33.431 ms 6 12.83.186.85 38.516 ms 51.138 ms 61.687 ms 7 12.122.5.190 48.626 ms 251.733 ms 38.487 ms 8 12.122.2.197 58.184 ms 82.183 ms^C You can also also do this do this by IP address fenrir:~ $ traceroute -ns 192.168.88.243 google.com traceroute to google.com (216.58.194.142) from 192.168.88.243, 64 hops max, 52 byte packets 1 192.168.88.1 4.658 ms 10.498 ms 3.633 ms 2 192.168.80.1 4.264 ms 58.660 ms 7.153 ms 3 172.26.96.161 105.557 ms 41.207 ms 32.243 ms 4 107.72.199.60 66.562 ms Which interface is used when IP address / interface is not specified is selected by the Service Order setting in the Network control panel.
  - lathiat 7y ago
    You can actually do this on linux pretty easily but it's not the default, it's sometimes called "source routing" Easy to setup with netplan and systemd-networkd, a little more complex to do manually.