I have a rather unusual networking challenge that I could use some help with. I have an isolated server that for security and compliance reasons has to be isolated from the network on physical level. It can be brought online by a L1 physical switch (something like https://www.bhphotovideo.com/c/product/1611245-REG/black_box_sw1041a_cat6_a_b_switch.html ) for a short period of time (a few seconds) and then it needs to be disconnected again. The issue I am running into - there doesn't appear to be an industry-wide metric of "how fast does the port come up when it's switched on?", so I am kind of stuck with trying different devices and seeing what works. Lots of setups have been tested: turns out that portfast is slower than just disabling spanning tree, 1G fiber is faster than hard-coded copper ports and MUCH faster than 10G fiber, static mac in fdb is a requirement, disabling errors and monitoring on interfaces helps too.…