Difference between revisions of "Linux utils"
From Wasya Wiki
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| − | + | = Utils = | |
| − | == | + | === Set date === |
| − | + | ||
| − | + | ||
sudo date --set "25 Sep 2013 15:00:00" | sudo date --set "25 Sep 2013 15:00:00" | ||
| − | + | ||
| + | === check disks on ubuntu === | ||
sudo lsblk | sudo lsblk | ||
| − | + | ||
| + | === check that a node is pingable in bash === | ||
while ! ping -c1 bjjc_spec_22.ubuntu14 &>/dev/null; do :; done ; | while ! ping -c1 bjjc_spec_22.ubuntu14 &>/dev/null; do :; done ; | ||
| − | + | ||
| + | === how to tell if port 80 is listening? === | ||
telnet? | telnet? | ||
| − | + | ||
| + | === how do I know if the system trusts the certificate? === | ||
you use curl. | you use curl. | ||
| − | + | ||
| + | === how to tell if port 80 is listening? What is listening on a particular port? === | ||
netstat -plnt | netstat -plnt | ||
| − | + | ||
| − | + | === ubuntu vpn === | |
| + | https://hide.me/en/vpnsetup/ubuntu/openvpn/ | ||
| + | |||
| + | === Find large files === | ||
find / -xdev -type f -size +100M | find / -xdev -type f -size +100M | ||
| − | + | ||
| + | === see timestamps in history === | ||
echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bashrc ; source ~/.bashrc | echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bashrc ; source ~/.bashrc | ||
* Generate large random file | * Generate large random file | ||
Revision as of 22:37, 15 December 2016
Contents
- 1 Utils
- 1.1 Set date
- 1.2 check disks on ubuntu
- 1.3 check that a node is pingable in bash
- 1.4 how to tell if port 80 is listening?
- 1.5 how do I know if the system trusts the certificate?
- 1.6 how to tell if port 80 is listening? What is listening on a particular port?
- 1.7 ubuntu vpn
- 1.8 Find large files
- 1.9 see timestamps in history
Utils
Set date
sudo date --set "25 Sep 2013 15:00:00"
check disks on ubuntu
sudo lsblk
check that a node is pingable in bash
while ! ping -c1 bjjc_spec_22.ubuntu14 &>/dev/null; do :; done ;
how to tell if port 80 is listening?
telnet?
how do I know if the system trusts the certificate?
you use curl.
how to tell if port 80 is listening? What is listening on a particular port?
netstat -plnt
ubuntu vpn
https://hide.me/en/vpnsetup/ubuntu/openvpn/
Find large files
find / -xdev -type f -size +100M
see timestamps in history
echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bashrc ; source ~/.bashrc
- Generate large random file
dd if=/dev/urandom of=/var/log/mongodb/randomFile bs=1M count=200
- Add ssh key to a server
cat ~/.ssh/id_rsa.pub | ssh user@hostname 'cat >> .ssh/authorized_keys'
- Add identity to a server
ssh-copy-id -i ~.ssh/key_name.pub user@host
- Create a user
su - <username> sudo visudo -f /etc/sudoers sudo adduser --disabled-password <username> (and there is deluser) (I don't think I need this: usermod -aG sudo username ) - for making him a sudoer
- Establish a simple ssh port forward
10.0.0.x is public, 10.0.1.x is private. Do:
sudo sysctl net.ipv4.ip_forward=1 sudo iptables -t nat -A PREROUTING -p tcp -d 10.0.0.229 --dport 2270 -j DNAT --to-destination 10.0.1.224:22 sudo iptables -t nat -A POSTROUTING -j MASQUERADE
- Reset Chef UI Password
sudo -u opscode-pgsql /opt/chef-server/embedded/bin/psql opscode_chef update osc_users set hashed_password = '$2a$12$y31Wno2MKiGXS3FSgVg5UunKG48gJz0pRV//RMy1osDxVbrb0On4W' , salt ='$2a$12$y31Wno2MKiGXS3FSgVg5Uu' where username ='admin';
and login with user 'admin' and password 'password'.
