雜七雜八的小筆記!

$ sudo vim /usr/share/applications/eclipse.desktop
============================================
[Desktop Entry]
Version=Photon
Name=Eclipse
Comment=Eclipse is an IDE
Exec=/opt/eclipse/eclipse
Icon=/opt/eclipse/icon.xpm
Path=/opt/eclipse/
Terminal=false
Type=Application
Categories=X-Red-Hat-Extra;Utility;Application;Development;
============================================

$ sudo vim /usr/share/applications/p4v.desktop
============================================
[Desktop Entry]
Version=Helix P4V/LINUX26X86_64/2018.2/1687764
Name=Perforce P4V
Exec=/opt/perforce/bin/p4v
Icon=/opt/perforce/lib/P4VResources/icons/p4v.svg
Path=/opt/perforce/
Terminal=false
Type=Application
Categories=X-Red-Hat-Extra;Utility;Application;Development;
============================================

# vim /etc/sysctl.conf
-----------------------------
fs.file-max = 65535
-----------------------------

# vim /etc/security/limits.conf
-----------------------------
* soft nofile 65535
* hard nofile 65535
root soft nofile 65535
root hard nofile 65535
jenkins soft nofile 65535
jenkins hard nofile 65535
-----------------------------

Google Chrome Install
1. Add Key:
# wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

2. Set repository:
# sudo sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google-chrome.list'
# sudo apt-get update

3. Install package: 
# sudo apt-get install -y google-chrome-stable

Reference: https://askubuntu.com/questions/510056/how-to-install-google-chrome

1. Install Packages
$ sudo yum install pptp pptp-setup

2. Config VPN Client.
$ sudo vim /etc/ppp/chap-secrets
-----------------------------------------
# Secrets for authentication using CHAP
# client        server  secret                  IP addresses
<VPN_USERNAME>    PPTP    <VPN_PASSWORD>        *
-----------------------------------------

Question 1:
$ ssh administrator@192.168.1.1 -p 5100
Unable to negotiate with 192.168.1.1 port 5100: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1

Question 2:
$ ssh administrator@192.168.1.1 -p 5100
Unable to negotiate with 192.168.1.1 port 5100: no matching cipher found. Their offer: 3des-cbc

Answer:
$ vim ~/.ssh/config
---------------------------------------------------------------------------
Host 192.168.1.1
     Ciphers 3des-cbc
     KexAlgorithms +diffie-hellman-group1-sha1 
---------------------------------------------------------------------------

$ echo "" > ~/.zsh_history & exec $SHELL -l

# vim /etc/ssh/sshd_config
============APPEND==============
UseDNS no
============APPEND==============

# service sshd restart

# sed -i "N;s/\n/ /g" text.txt

# vim /etc/network/interfaces
===================================                             
auto lo
iface lo inet loopback

auto br0 
iface br0 inet static
    address 172.17.11.1
    netmask 255.255.254.0
    gateway 172.17.10.254
    dns-search dreamtails.local
    bridge_ports eth0
    bridge_stp off
    post-up route add default via 172.17.10.254 dev br0 

auto br1 
iface br1 inet dhcp
    bridge_ports eth1
    bridge_stp off 
    post-up route del default dev br1
===================================

# vim /etc/dhcp/dhcpd6.conf
===========add==============
．．．．．．
log-facility local0;
．．．．．．
===========add==============

$ sudo vim /etc/network/interfaces
=============================
# interfaces(5) file used by ifup(8) and ifdown(8)                              
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 172.17.11.1
netmask 255.255.254.0
gateway 172.17.10.1
dns-search dreamtails.local     # equal to "search" in /etc/resolv.conf

auto eth1
iface eth1 inet dhcp
post-up route del default dev eth1
==============================

1. Install packages
# yum install dhcp*
# yum install radvd

# mkdir -p /tmp/cores
# chmod a+rwx /tmp/cores
# echo "/tmp/cores/%e.%p.%h.%t.core" > /proc/sys/kernel/core_pattern
------------------------
%p: pid
%: '%' is dropped
%%: output one '%'
%u: uid
%g: gid
%s: signal number
%t: UNIX time of dump
%h: hostname
%e: executable filename
------------------------

# ulimit -c unlimited
# kill -s SIGSEGV $$

Reference: https://sigquit.wordpress.com/2009/03/13/the-core-pattern/

$ sudo vim /etc/network/interfaces
-------------------------------------------------------------------------
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 10.10.100.1
netmask 255.255.0.0
gateway 10.10.0.254
#post-up route add default via 10.10.0.254 dev eth0

auto eth1
iface eth1 inet dhcp
post-up route del default dev eth1
-------------------------------------------------------------------------

If the /dev/sdb is USB device.

# sudo -i

# fdisk /dev/sdb
--> n    (Create partition)
．．．．．．．
--> w

CentOS 7:
# yum install -y numactl
# numactl -H

Ubuntu 14.04:
# apt-get install numactl
# numactl -H

1. Download i386 skype and teamviewer .deb as follows,
    - skype.i386.deb
    - teamviewer.i386.deb

2. Install GDebi package
# apt-get install -y gdebi

3. Update the i386 .deb by GDebi
# gdebi skype.i386.deb
# gdebi teamviewer.i386.deb

4. Install skype and teamviewer on Ubuntu 14.04 64-bit
# dpkg -i skype.i386.deb
# dpkg -i teamviewer.i386.deb

# vim /etc/gai.conf

uncomment line 54
from
-------------------------------------------------------------------
．．．．．．．．．
#
#    For sites which prefer IPv4 connections change the last line to
#
# precedence ::ffff:0:0/96  100
．．．．．．．．．
-------------------------------------------------------------------

Physical interface (em1) setting:
# vim /etc/sysconfig/network-scripts/ifcfg-em1
-------------------------- 
DEVICE=em1
HWADDR=xx:xx:xx:xx:xx:xx
ONBOOT=yes   
TYPE=Ethernet
BRIDGE=br0
DEFROUTE=no
-------------------------- 

Example 1:
# virt-install --connect qemu:///system --os-type=linux --ram 2048 --vcpus=2 --cpu host --noautoconsole --force --import --disk path=/tmp/CentOS6.qcow2,device=disk,bus=scsi,format=qcow2 --os-variant=rhel6 --name test1

Example 2:
# virt-install --connect qemu:///system --os-type=linux --ram 2048 --vcpus=2 --cpu host --noautoconsole --force --import --disk path=/tmp/CentOS6.qcow2,device=disk,bus=virtio,format=qcow2 --os-variant=rhel6 --network model=virtio,bridge=br0 --name test2_for_br0