Gigantic amount of ttys(ReadyNASOS 6.4.0)

[bestgo]

hi there,

OS: ReadyNAS OS 6.4, about the following issue, it's better to modify kernel config to resolve it.

https://github.com/scaleway/image-debian/issues/27

root cause:

That's caused by CONFIG_LEGACY_PTYS=y and CONFIG_LEGACY_PTY_COUNT=256 in the kernel configuration. These days it's sufficient to rely on CONFIG_UNIX98_PTYS=y only.

$ls -l /sys/devices/virtual/tty/ |grep pty

drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya0
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya1
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya2
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya3
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya4
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya5
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya6
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya7
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya8
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptya9
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyaa
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyab
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyac
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyad
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyae
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyaf
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb0
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb1
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb2
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb3
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb4
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb5
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb6
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb7
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb8
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyb9
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyba
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptybb
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptybc
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptybd
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptybe
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptybf
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc0
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc1
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc2
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc3
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc4
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc5
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc6
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc7
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc8
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyc9
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyca
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptycb
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptycc
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptycd
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyce
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptycf
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd0
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd1
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd2
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd3
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd4
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd5
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd6
drwxr-xr-x 2 root root 0 Dec 25 12:50 ptyd7

 ...

-thanks

[StephenB]

What problem is this causing you?

[bestgo]

yes, i know it's harmless, tty devices just print a long list when i display tiems under /dev and show systemctl.

[mdgm-ntgr]

I have passed on this feedback. This particular problem would understandably be a low priority one.