Java in cloud

I've tried new Spring Framework (Wweb MVC 5) with Standard AppEngine runtime (Java8). Unfortunately "most standard" approach to initialise application with extending AbstractAnnotationConfigDispatcherServletInitializer  class has failed miserably: public class EntryPoint extends AbstractAnnotationConfigDispatcherServletInitializer {     @Override     protected Class<?>[] getRootConfigClasses() {         return new Class<?>[]{RootConf.class};     }     @Override     protected Class<?>[] getServletConfigClasses() {         return new Class<?>[]{WebConf.class};     }     @Override     protected String[] getServletMappings() {         return new String[]{"/"};     } } The failure was (it really seems to be platform rather than Spring issue): org.eclipse.jetty.annotations.ServletContainerIn...

How to tag code with specific key PGP for signature (especially when there is discrepancy between git email address and PGP key email address): git tag -a v1.2.3 -m "Tagging something" -u your-key-id git show v1.2.3 git push origin --tags How to 

You need to install OpenSSH client: root@OpenWrt:~# opkg update root@OpenWrt:~# opkg install openssh-client Now OpenSSH client replaced DropBear client: root@OpenWrt:~# ls -l /usr/bin/ssh -rwxr-xr-x    1 root     root        590667 May 24 14:54 /usr/bin/ssh root@OpenWrt:~# ls -l /rom/usr/bin/ssh lrwxrwxrwx    1 root     root            16 Aug 19  2016 /rom/usr/bin/ssh -> ../sbin/dropbear root@OpenWrt:~# ls -l /overlay/upper/usr/bin/ssh -rwxr-xr-x    1 root     root        590667 May 24 14:54 /overlay/upper/usr/bin/ssh Can you spot a difference: root@OpenWrt:~# ssh usage: ssh [-1246AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]            [-D [bind_address:]port] [-E log_file] [-e escape_char]            [-F configfile] [-I pkcs11] [-i identity_file...

How to import PGP public key? gpg --import 99242560.key gpg: key DB698D7199242560: public key "David M. Shaw <dshaw@jabberwocky.com>" imported gpg: Total number processed: 1 gpg:               imported: 1 gpg: marginals needed: 3  completes needed: 1  trust model: pgp gpg: depth: 0  valid:   1  signed:   0  trust: 0-, 0q, 0n, 0m, 0f, 1u gpg: next trustdb check due at 2018-01-09 How to verify the file signature? gpg --verify paperkey-1.4-win32.zip.sig gpg: assuming signed data in 'paperkey-1.4-win32.zip' gpg: Signature made 09/06/16 02:01:14 GMT Daylight Time gpg:                using RSA key FEA78A7AA1BC4FA4 gpg: Good signature from "David M. Shaw <dshaw@jabberwocky.com>" [unknown] gpg: WARNING: This key is not certified with a trusted signature! gpg:          There is no indication that the signature belongs to the owner. Pr...

As usual Arch Linux does not install a binary that you might not need to have. So we need to run: [root@archt20 ~]# pacman -S smartmontools Then simply: [bart@archt20 ~]$ smartctl -a /dev/sda It is also worth to install hdparm [root@archt20 ~]# pacman -S hdparm [root@archt20 ~]# hdparm /dev/sda /dev/sda:  multcount     = 16 (on)  IO_support    =  1 (32-bit)  readonly      =  0 (off)  readahead     = 256 (on)  geometry      = 60801/255/63, sectors = 976773168, start = 0

I was playing with go and it turned out that my Linux does not have gcc that is necessary to compile code that uses cgo. Solution as always with Arch Linux was straightforward: [bart@archt20 ~]$ sudo pacman -S base-devel :: There are 25 members in group base-devel: :: Repository core    1) autoconf  2) automake  3) binutils  4) bison  5) fakeroot  6) file  7) findutils  8) flex  9) gawk  10) gcc  11) gettext  12) grep  13) groff  14) gzip    15) libtool  16) m4  17) make  18) pacman  19) patch  20) pkg-config  21) sed  22) sudo  23) texinfo  24) util-linux  25) which Enter a selection (default=all):

Main purpose is to have SSH tunel to my remote home network. Update root@OpenWrt:/tmp# wget http://downloads.openwrt.org/chaos_calmer/15.05.1/ar71xx/generic/openwrt-15.05.1-ar71xx-generic-tl-wr1043nd-v1-squashfs-sysupgrade.bin Connecting to downloads.openwrt.org (78.24.191.177:80) openwrt-15.05.1-ar71 100% root@OpenWrt:/tmp# ls -la -rw-r--r--    1 root     root       3473412 Feb 17 10:11 openwrt-15.05.1-ar71xx-generic-tl-wr1043nd-v1-squashfs-sysupgrade.bin root@OpenWrt:/tmp# md5sum openwrt-15.05.1-ar71xx-generic-tl-wr1043nd-v1-squashfs-sysupgrade.bin f5f073251dd3b191e9ed806cb95de029  openwrt-15.05.1-ar71xx-generic-tl-wr1043nd-v1-squashfs-sysupgrade.bin Unlocking firmware ... Writing from openwrt-15.05.1-ar71xx-generic-tl-wr1043nd-v1-squashfs-sysupgrade.bin to firmware ... Rebooting ... Turning router into access point I've edited network config file: config interface 'lan'         option ifname 'eth0.1' ...

https://www.ssllabs.com/ssltest/analyze.html?d=bart.prokop.name The one domain that cannot get behind cloud flare... but still pretty secure.

OVH recently added IPv6 addresses for all their VPS hosts. Unfortunately they did not provided the instructions how to add IPv6 support for their Arch Linux distribution. Here is what have worked for me (highlighted are changes to default file value): # cd /etc/systemd/network # cp eth0-dhcp.network eth0-dhcp.network.ORIGINAL # cat eth0-dhcp.network [Match] Name=eth0 [Network] DHCP= ipv4 [DHCP] UseMTU=true [Address] A ddress=2001:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:1234 /64 [Route] Gateway= 2001 :xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:0001 # networkctl status et0 Please note that default OVH recommendation (i.e. /128 mask and static route to gateway) is not possible to achieve with systemd networking. That is why I went with /64 mask and simple Gateway option.

We need to create new "simple" systemd service. It is just a single text file. # pwd /etc/systemd/system Create file: whatever_you_want.service with similar content [Unit] Description=webserver Daemon [Service] ExecStart=/opt/jdk1.8.0_101/bin/java -Djava.security.egd=file:/dev/./urandom -jar /root/spring-boot-1.0-BETA.jar User=user [Install] WantedBy=multi-user.target That's really it!. Now you can use following commands to control newly created service. To start the service # systemctl start whatever_you_want.service To auto start the service # systemctl enable whatever_you_want.service [root@vps]# systemctl enable flex-demo Created symlink /etc/systemd/system/multi-user.target.wants/whatever_you_want.service → /etc/systemd/system/whatever_you_want.service. To stop autostart # systemctl disable whatever_you_want.service To stop the service # systemctl stop whatever_you_want.service To restart the service ...