Shaun's Wiki

Because SSH is incredible.

# Using connect-proxy as a socks proxy (tunneling ssh over http proxy to an ssh server on port 1.2.3.4:443)
Host 1.2.3.4
  ProxyCommand connect-proxy -H proxy:3128 %h %p
  Port 443
  User shaun
 
# -W can be used for raw port-forwarding on OpenSSH 5.4 and higher
Host internal.server
  HostName internal.server.com
  User shaun
  ProxyCommand ssh shaun@intermediary.server.com -W %h:%p
 
# Here's the old way, with netcat
Host internal.server
  HostName internal.server.com
  User shaun
  ProxyCommand ssh shaun@intermediary.server.com nc %h %p
 
# New to OpenSSH 7.3 and higher is the ProxyJump commmand, which does the same, but with multiple possible intermediaries
Host internal.server
   HostName internal.server.com
   ProxyJump shaun@intermediary1.server:22,shaun@intermediary2.server:22
   User shaun

ssh -NTCf -w 0:0 <destination>
 
# Machine A
ip link set tun0 up
ip addr add 10.0.0.100/32 peer 10.0.0.200 dev tun0
 
# Machine B
ip link set tun0 up
ip addr add 10.0.0.200/32 peer 10.0.0.100 dev tun0
 
# Add a route for target network on Machine B
ip route add 10.0.0.0/24 via 10.0.0.200
 
#This allows us to send packets from Machine B to any IP address on Network A, via Machine A. 
#To ensure that packets have a route back to Machine B add an arp entry on Machine A:
 
arp -sD 10.0.0.200 eth0 pub
 
#This sets a published arp destination for 10.0.0.200 to Machine A (proxy-ARP). 
 
# Kernel packet forwarding must be enabled for the routing bits
echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward

ssh-copy-id -i .ssh/id_rsa.pub user@server.com

xfs
ext4 recovery

dmidecode --type 17

Sample output:

# dmidecode 2.12
SMBIOS 2.7 present.
 
Handle 0x003B, DMI type 17, 34 bytes
Memory Device
        Array Handle: 0x002C
        Error Information Handle: Not Provided
        Total Width: 72 bits
        Data Width: 64 bits
        Size: 32 GB
        Form Factor: DIMM
        Set: None
        Locator: D0
        Bank Locator: /SYS/MB/P0
        Type: DDR3
        Type Detail: Synchronous
        Speed: 1066 MHz
        Manufacturer: Samsung
        Serial Number: 366112E5
        Asset Tag:
        Part Number: M393B4G70BM0-YH9
        Rank: 1
        Configured Clock Speed: 1066 MHz

openssl x509 -in certificate.crt -out certificate.pem -outform PEM

echo FakeProcName > /tmp/cmdline
mount -n --bind -o ro /tmp/cmdline /proc/<pid>/cmdline
 
ps -ef | grep FakeProcName

curl -s https://raw.githubusercontent.com/sivel/speedtest-cli/master/speedtest.py | python -

Oracle Enterprise Linux