Generate QR Code for WiFi

 install ‘qrencode’ command. $ sudo apt install qrencode generate QR code png $ qrencode -o image.png ‘WIFI:T:WPA;S:SSID;P:PASSWORD;;’ Parameter Example Description T WPA Authentication type; can be WEP or WPA, or leave empty for no password. S SSID Network SSID. Required. P pasXXXX Password, ignored if T is left blank. H true Optional. True if the network SSID is hidden.

Change ssh port , CentOS 8

Cent OS support firewall-cmd & SeLinux, Its environment understood not easily.  ssh port changing is very easy !Edit /etc/ssh/sshd_config. Find “# Port 22″ and change to Port xxxx” (xxxx is your specified). # If you want to change the port on a SELinux system, you have to tell # SELinux about this change. # semanage port -a -t ssh_port_t -p tcp #PORTNUMBER # Port xxxx <— Change your specified port number. #AddressFamily any #ListenAddress #ListenAddress :: if execute “sudo systemctl restart sshd.service”, you can find error messages. And execute “sudo systemctl status sshd.service” ● sshd.service – OpenSSH server daemon Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled) Active: activating (auto-restart)…

Setup OneDrive in Ubuntu 18.04

Install OneDrive deb package. $ sudo apt install onedrive Sync OneDrive on user directory. $ onedrive Authorize this app visiting: Login to Your OneDrive Account then copy displayed URL of white page. Paste to excution terminal. enable user systemctl (daemonic). After syncing, execute following daemon $ systemctl –user enable onedrive $ systemctl –user start onedrive Reset Account or Change password or Login ID $ systemctl –user stop onedrive If do not need backup $ rm -r .config/onedrive else $ mv .config/onedrive ‘backup directory/’ reexcute ‘onedrive’ after these step.

Ubuntu LTS update

Release upgrade ex. 18.04.x -> 20.04 $ sudo do-release-upgrade -d Minor upgrade 16.04.x -> 16.04.3 ex. 16.04.2 -> 16.04.3 20.04, Not available now.(June 10) DeskTop: $ sudo apt install –install-recommends linux-generic-hwe-16.04 xserver-xorg-hwe-16.04 Server: $ sudo apt install –install-recommends linux-generic-hwe-16.04

Ubuntu 18.04 network setting

Use Netplan Put under directory ‘/etc/netplan/’.example; 50-cloud-init.yamlAfter Edit, command “netplan”  for checking option “netplan try” and for actual seting “netplan apply”. To let the interface named ‘enp2s0’ get an address via DHCP: network version: 2 renderer: networkd ethernets: enp3s0: dhcp4: true To instead set a static IP address, use the addresses key, which takes a list of (IPv4 or IPv6), addresses along with the subnet prefix length (e.g. /24). Gateway and DNS information can be provided as well: network: ethernets: enp2s0: dhcp4: no dhcp6: no addresses: [] gateway4: nameservers: addresses: [] #if use static route routes: – to: via: version: 2 Connecting to an open wireless network…

icmp type

◆ ICMPのType 一覧表 Type 内容 意味 種類 0 Echo Reply エコー応答 Query 3 Destination Unreachable 宛先到達不能 Error 4 Source Quench 始点抑制 Error 5 Redirect 最適経路への変更指示 Error 8 Echo Request エコー要求 Query 9 Router Advertisement ルータ通知 Query 10 Router Solicitation ルータ要求 Query 11 Time Exceeded TTL超過によるパケット破棄の報告 Error 12 Parameter Problem パケットパラメータにおけるエラー Error 13 Timestamp タイムスタンプ Query 14 Timestamp Reply タイムスタンプ応答 Query 15 Information Request インフォメーション要求 Query 16 Information Reply インフォメーション応答 Query 17 Address Mask Request アドレスマスク要求 Query 18 Address Mask Reply アドレスマスク応答 Query