6443
kube-api
TCP · 0x192B
Port 6443 — kube-api
Dev and ops
Port 6443 carries Kubernetes API server over TCP. Above 1023, so an ordinary user can open it.
1024–49151. Meant to be applied for, though some numbers here are custom by habit.
Where it sits in 65535
A port number is 16 bits, so it stops at 65535. The narrow band at the left is everything up to 1023.
065535
- Service
- Kubernetes API server (kube-api)
- Kind
- Dev and ops
- Protocol
- TCP
- Range
- Registered
- Root needed
- No
- Hexadecimal
- 0x192B
- Binary
- 0001100100101011
- Two bytes
- 25 · 43
Same kind
Ports that development and operations tools open.
Ports next to it
How to read this
- A port number is 16 bits, so it runs 0 to 65535. There is no port 65536.
- Opening anything at or below 1023 needs root on Unix.
- Plain and encrypted often live on different numbers — 80 and 443, for one.
- Numbers like 3000 and 8080 were never registered; those are marked as custom.
Frequently asked questions
Q. What is port 6443 used for?
Kubernetes API server (kube-api) uses it, over TCP.
Q. Does opening port 6443 need root?
No. It is above 1023, so an ordinary user can open it.
Q. Which range does port 6443 fall in?
Registered (1024–49151). In hex it is 0x192B.
Q. Does port 6443 have a twin?
Not a separate one. It either was encrypted from the start or negotiates TLS on the same number.