Deleted Luci by mistake

Unfortunately, when I wanted to free some space over SSH by deleting packages
with “ppp” in their names it also deleted luci and its webpanel :

root@Arduino:~# opkg -recursive remove *ppp*  <<<< DON'T USE THIS COMMAND ...
Removing package ppp-mod-pppoe from root...
Removing package kmod-pppoe from root...
Removing package kmod-pppox from root...
Removing package luci-app-arduino-webpanel from root...
Removing package luci from root...
Removing package luci-proto-ppp from root...
Removing package kmod-ppp from root...

Is there a way to get it them back without reflashing everything? I already tried:

opkg install luci

AND IF WE ARE AT IT:
Is there a list of packages which are (not) really necessary. Of course all depends on individual usage, but maybe someone made a list/description of the (essential) packages of the YUN?

And will it help to remove them over Luci/SSH or do I have to delete them from the file we use for reflashing? If we need to delete them from the reflash-file: Can you give me a link or describe how to do it?

It is probably easiest to just use failsafe mode and run reset-to-factory-anyway, or just reflash the image.

If you really want to go the re-install route, post the error you get when you tried opkg install luci. opkg should work in this situation, it will install any missing packages that luci needs.

Of course all depends on individual usage,

EXACTLY! Some would consider luci totally optional, and use uci to set things up from a command line. Even more hard core would be dumping uci and just editing the config files by hand.

To get a custom setup installing the stock image and then removing things carefully is the easiest, otherwise you would need to build your own image.

Here is the error:

root@Arduino:~# opkg install luci
Unknown package 'luci'.
Collected errors:
 * opkg_install_cmd: Cannot install package luci.
root@Arduino:~#

I know the reset-script, but what is the failsafe-mode?

opkg update should take care of that error.

You get to failsafe by loading the yunserialterminal sketch over USB and using the serial monitor, PuTTY, minicom or picocom. When you press the yunrst button you see the boot process, a press f prompt will come by, you press f and enter :fearful: you do need to be quick it only pauses for a second or two.

I didn't forget opkg update ;) It didn't work

Forget about it. I've already reset the yun, because debugging/.. takes longer than that