1.9 KiB
1.9 KiB
| description |
|---|
| this week we configured dhcp01-nathan to run the dhcp server. now wks01 uses dhcp rather than static IP assignment |
Lab04 - DHCP
DHCP configuration
- connect to dhcp01-nathan via puTTY
sudo yum install dhcp- configure
/etc/dhcp/dhcpd.conffile
- start&enable dhcp
- configure dhcp on firewall
- configure wks01-nathan to use DHCP instead of static IP
to start dhcp
systemctl start dhcpd
to check status of dhcp
systemctl status dhcpd
configure dhcp to start on boot
systemctl enable dhcpd
configure dhcp on firewall
firewall-cmd --add-service=dhcp --permanentfirewall-cmd --reloadfirewall-cmd --list-all
search for dhcp logs from wks01-nathan
sudo cat /var/log/messages | grep wks01-nathan
release dhcp
ipconfig /release
renew dhcp
ipconfig /renew
filtering dhcp messages in wireshark
udp.port==67
Disable root access via ssh
nano /etc/ssh/sshd_config- change
PermitRootLoginfrom yes to no and uncomment systemctl restart sshd
File Permissions
how to create a group
groupadd [groupname]
how to add a user to a group
usermod -aG [groupname] [username]
how to change the owner of a file
chown filename [username]
how to change the group of file
chgrp filename [groupname]
Changing file permissions
Method 1: using bit values
- Read: 4
- Write: 2
- Execute: 1 Add up the numbers to set permissions for each accessor (owner/group/everyone else)
example: chmod 640 file.txt give read/write to owners, read to group members, and no access to everyone else
Method 2: adding/removing file permissions individually
chmod u+/-(r/w/x) [filename]- users (owner)chmod g+/-(r/w/x) [filename]- groupchmod o+/-(r/w/x) [filename]- others (everyone else)
example: chmod g+w file.txt gives write permissions to the group of file.txt