Treiberenwicklung in C HW 2

Question 1

Was ist erforderlich, dass Linux mit SSH zu erreichen ist?

Answer 1

Kernel Settings 
 - All VIRTIO settings
 - TCP/IP networking
 - Networking features overall
 - MULTIUSER config
Busybox
 - ifconfig
 - route
 - udhcpc (client!)
Dropbear

Question 2

What is the devpts filesystem mounted at /dev/pts used for when dropbear is configured with –enable-openpty (default)?

Answer 2

pts is used as a virtual terminal to display the output of dropbear on the kernel terminal.

Question 3

Mit welchem Tool ermöglicht man die Kommunikation über SSH mit der Maschine?

Answer 3

Dropbear is a relatively small SSH server and client

Question 4

Befehl über den Maschine über SSH erreichbar ist?

Answer 4

ssh -o StrictHostKeyChecking=off root@localhost -p 22222 “$@”

Question 5

How can you display the public key portion of the key file?

Answer 5

Change into your user directory with cd

Use cat .ssh/id_rsa.pub

Question 6

Which file within a user’s home directory is used by the SSH server to know which public keys are authorized for the respective user?

Answer 6

The authorized_keys file in the ~/.ssh directory.

Question 7

How is the DHCP lease applied to the interface by udhcpc?

Answer 7

Once the udchpc obtained or lost a lease it will run a script. This script should configure the system ip, gateway, resolv.conf etc. Busybox provides a sample script, which is placed in the examples/udhcp/ directory after building it.