danish-rehman

YELLOW="\[\033[0;33m\]"

CLEAR="\[\033[0;0m\]"

PS1="\$(date +%H:%M) \w$YELLOW \$(parse_git_branch)$CLEAR \$ "

danish-rehman

#Diff with master
>> git diff master — filename

# Checkout submodule
>> git submodule update

# Undo last commit
>> git reset —soft HEAD~1

# Add remote repo

danish-rehman

# Basic get request
>> curl -v  http://www.test.com

# Get request with a header
>> curl -v http://www.test.com?debug=1 -H "Cookie: Key=Value;”

danish-rehman

# (Maximum TCP Sender Window)
>> /proc/sys/net/ipv4/tcp_wmem 
   4096	     16384     4194304

(Maximum TCP Receive Window)
>> /proc/sys/net/ipv4/tcp_rmem 
   4096	     87380     6291456

danish-rehman

# current receiver window size 
>> sysctl -n net.ipv4.tcp_rmem
  4096	  87380	   2063584 (2Mb)

# current sender window size
>> sysctl -n net.ipv4.tcp_wmem
  4096	  87380	   2063584 (2Mb)

# maximum segment size
>> sysctl -n net.ipv4.tcp_app_win

danish-rehman

# Current receiver window size (12Mb)
>> sudo su
>> echo 'net.ipv4.tcp_rmem= 4096 87380 12582912' >> /etc/sysctl.conf
>> sysctl -p

# Current sender window size (12Mb)
>> sudo su
>> echo 'net.ipv4.tcp_rmem= 4096 87380 12582912' >> /etc/sysctl.conf
>> sysctl -p

danish-rehman

# SO_SNDBUF
# Cannot exceed maximum size available in kernel config
# Kernel config:  /proc/sys/net/core/rmem_max
                  212992

# SO_RCVBUF
# Cannot exceed maximum size available in kernel config
# kernel config:  /proc/sys/net/core/wmem_max 
                  212992

danish-rehman

>> cat /proc/sys/net/ipv4/tcp_fin_timeout
   60 seconds

# To change the value 
>> echo 30 >  /proc/sys/net/ipv4/tcp_fin_timeout

danish-rehman

>> echo 30 > /proc/sys/net/ipv4/tcp_keepalive_intvl

danish-rehman

>> echo 5 > /proc/sys/net/ipv4/tcp_keepalive_probes