Board specifications at and available at

Example code in language c can be found at


Download kendryte-standalone-sdk, kendryte-standalone-demo and kendryte-gnu-toolchain and kflash (needs python3; pip3 install pyserial pyelftools kflash; windows kflash)

  • if both are installed inside directory $HOME/kendryte/
    • cd kendryte/kendryte-standalone-sdk/build/
    • cmake .. -DTOOLCHAIN=$HOME/kendryte/kendryte-gnu-toolchain/bin/ -DPROJ=apu
    • make
    • kflash -p /dev/cu.usbserial-00004014B -B goE apu.bin -b 2000000
    • replace /dev/cu.usbserial-00004014B by your usb port (second port of the two ports of maiix go has to be used)

Playing with builtin APU (audio processing unit) and circular mic array (6 mics + center mic; specs, buy)

+----------+  +----------+  +------------+  +-------+  +-----+ +--------------------- +  +-----+  +-----+
| 8ch in | - > | buffer | - > | DAS BF | -> | gain | -> | FIR | -> | DownSample | -> | FIR | -> | FFT |
+----------+  +----------+  +------------+  +-------+  +------+ +---------------------+  +------+ +------+
Gain vs. Frequency
Impulse Response
Filter settings (

modify fir_neg_one[] of init.c in sdk demo apu:
forum: signed fixed point number between -1 ~ 1
so use of int16_t giving -32768 …. 32768 matches the output of TFilter website (choose C/C++ array, int, 16 bit):

uint16_t fir_neg_one[] = { // -32768
0x8000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
uint16_t fir_one[] = { // 32767
0x7fff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
uint16_t fir_half[] = { // 16384
0x4000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

int16_t fir_lowpass_signed[] = { // 44100 Hz 17 taps pass 0-5000, stop 10000-22050

apu_dir_set_prev_fir((uint16_t *)fir_lowpass_signed); //

… to be continued (speech direction detection using apu, displayed by leds of mic array)

Server monitoring with graphical output required, but no need to run a monitoring suite like nagios? With existing debian lamp server you might want to use SmokePing.

Setup is fairly easy:

  • apt-get install smokeping
  • edit /etc/smokeping/config.d/General
    let cgiurl point to your server https://your_domain.tld/cgi-bin/smokeping.cgi
  • edit /etc/smokeping/config.d/Targets and define the servers which should be monitored
  • restart smokeping: systemctl restart smokeping (or smokeping –restart)
  • open https://your_domain.tld/smokeping/smokeping.cgi

Add password protection:

  • edit /etc/apache2/conf-available/smokeping.conf and add two Location sections:
    <Location /cgi-bin/smokeping.cgi>
    AuthUserFile /etc/apache2/your_password_file
    AuthName “protected”
    AuthType Digest
    AuthDigestProvider file
    require valid-user
    <Location /smokeping/smokeping.cgi>
    … (see above)
  • htdigest -c /etc/apache2/your_password_file “protected” your_user
  • apache2ctl configtest
    apache2ctl graceful

Credits go to Tobi Oetiker, the author of this well made tool!


some notes:

very slow disk access inside vm might be caused by balanced power plan (which is install default in server 2008r2, 2012r2 hyperv core).
use powercfg.exe -l to check powerplan and powercfg -s to set another plan, e.g. performance; check with crystalldiskmark

running some time virtual disks tend to get to small. On server 2012r2 powershell has:
get-vhd -path …, resize-vhd -path -sizebytes …GB, optimize-vhd

before moving a vhd(x) file, display acl lists using icacls (to be able to restore permissions iacl …./grant …)

… net use z:  \\\sharename * /user:your_name (and net use z: /delete)

partitions inside a vhd may be resized with diskpart
– sel vdisk file=….
– attach vdisk
– sel last partition and the corresponding volume
– extend
– lis par (to check)
– detach

Excellent (!) main reference

Special case ts-221 (and probably all devices with 1GB RAM): kernel of debian stretch 4.9 (also stretch-backports 4.17) seems to fail with memory above 768M on qnap arm
(discussion:!topic/linux.debian.ports.arm/vSaO642z8aY); dmesg shows
BUG: Bad rss-counter state mm

  • use jessie installer in expert mode and install stretch (offered by jessie installer as testing release)
  • before reboot
    • either switch to older kernel as described below
    • or use only 768MB of 1024MB ram to avoid this bug
      mount /dev and /proc (maybe /sys) inside installation directory and chroot into installation directory

      • copy /usr/share/doc/u-boot-tools/examples/qnap_ts119-219.config
        to /etc/fw_env.config (assuming package u-boot-tools has been installed)
      • then run fw_printenv bootargs which returns something like
        bootargs=console=ttyS0,115200 root=/dev/ram initrd=0xa00000,0x900000 ramdisk=34816
      • now use fw_setenv to add linux kernel boot parameter mem=768M by adding mem=768M to output of fw_printenv
        fw_setenv bootargs “console=ttyS0,115200 root=/dev/ram initrd=0xa00000,0x900000 ramdisk=34816 mem=768M”
        (takes some time to write to flash)
      • check with fw_printenv that bootargs still contains the original arguments (plus mem=768M)
      • reboot (check with free -h and cat /proc/cmdline; dmesg: Memory: … 0K highmem)
      • maybe, this has to be repeated after every linux kernel update (verify withc fw_printenv bootargs if mem=768M ist still there)


In case flash-kernel returns Failed to obtain MAC address, run either
ubootcfg -b 0 -f /dev/mtdblock4 -o – | grep “^ethaddr=” | sed “s/^ethaddr=//”
or fw_printenv ethaddr
which returns the mac address stored in flash; then run
iface_set_mac eth0 YOUR_QNAP_MAC_FROM_FLASH

Recovery: run this iso from qnap wiki page inside a vm or install minimal debian with isc-dhcp-server and tftpd-hpa.

To make sure that an existing harddisk gets properly reconfigured use installer option (removal of raid partitions)
guided – entire disk

  • one partion with btrfs and option noatime
  • in case of error see below

Workaround (ok for devices without fan): If status led remains blinking red-green create /etc/rc.local, make it executable
qcontrol –direct statusled greenon
exit 0

Solution (fixes led, buzzer and fan): # qcontrol needs stretch backports: apt-get -t stretch-backports install qcontrol, so add to /etc/apt/sources.list

deb stretch-backports main

and /lib/systemd/system/ is broken: replaces lines

ConditionPathExists=/dev/input/by-path/platform-gpio_keys-event (kernel 4.9) or platform-gpio-keys-event (kernel 3.16)
and afterwards run
dpkg –configure qcontrol

In case one disk is used for the system and a second disk is used for data: mount the second disk in /etc/fstab with option noauto (else the system will not start if the data disk has been removed)

Install smartmontools and check disk with smartctl -a /dev/sdXN

Special case ts-221: does not run with kernel 4.9, so run debian stretch with kernel 3.6 -or use bootarg mem=768M as described above
(latest discussion:!topic/linux.debian.ports.arm/vSaO642z8aY)

  • first install debian jessie (as described on for stretch but replace stretch by jessie in download links)
    • copy /boot/*, /lib/modules/*, /usr/lib/linux-image-* into a tar archive and save it on an external storage device
  • second, flash again the jesssie installer, but now run it in expert mode and install debian stretch
    • before rebooting the second last step “finish install or so” open console 2 (keys <ctrl> + <a>, then key <2>)
      • copy the saved contents of first installation (tar archive) into running installation
      • edit /usr/share/flash-kernel/functions: change force=”no” to force=”yes”
      • run update-initramfs -u -k 3.16..0-6-kirkwood (and probably you get a message to add “-t” as additional argument)
        later if kernel/initramfs get renewed, it is required to run afterwards: update-initramfs -u -k $(uname -r)

the installer does not cope well with already used disks (guided, use whole disk should work); if not, start installer in expert mode and add fdisk as installer component
(in case of running debian stretch wipefs -a removes all kind of signatures; but do double check that you will not wipe the wrong partition!)

  • open shell 2 and run cat /proc/partitions
  • use fdisk to create a new partition table (dos format) and create one big primary partion
  • create a filesystem on this partition with mkfs.ext2
  • reboot!!! And then run installer again in standard mode

Some qnap models may take more than 15 minutes until kernel and initrd are written to flash. – First reboot after installation might by succesful, even if power led keeps blinking red-green and buzzer remains silent. Led and buzzer need installation of qcontrol from backports and patched qcontrold.service file as described above.

Enable quota: btrfs quota enable /backup; btrfs quota enable /backup2
Display disk usage: btrfs sub list /backup; btrfs qgroup show /backup
unused because of to much memory usage when deleting snapshots

mkfs.btrfs shows after creation of filesystem whether incompatibilities with current kernel exist; use -O ^prop1,^prop2 if properties prop1,prop2 ar not compatible; (use wipefs to remove the newly created filesystem and recreate it using -O ^…)

Convert btrfs single partition filesystem to btrfs raid1 during debian install

  • use installer to create a btrfs root partition (noatime option) on a single partition
  • use installer to create on second disk a partition of same size without mountpoint
  • let installer write new partitions to disk
  • open second ssh connection and choose shell
    • btrfs filesystem show
    • df -h
    • btrfs device add -f /dev/PARTITION_ON_SECOND_DISK /target
    • btrfs balance start -dconvert=raid1 -mconvert=raid1 /target
    • btrfs filesystem show

Recover from failure of one drive of root filesystem on btrfs raid1

  • difficulty: if / gets remounted ro because of filesystem errors reboot into installer is required
  • prepare for rescue with installer
    • mkdir /var/backups/flash-installer
    • cd /tmp
    • wget
    • dmesg |grep SoC
      ID=0x… displays wether kernel 6282 or 6281 is used
      cp initrd /var/backups/flash-installer/mtd2
      cp kernel-6282 /var/backups/flash-installer/mtd1 (or use kernel 6281)
    • to boot into installer run:
      cat /var/backups/flash-installer/mtd1 >/dev/mtdblock1
      cat /var/backups/flash-installer/mtd2 >/dev/mtdblock2
    • to restore installed system when running installer run:
      mount YOUR_PARTITION /mnt
      cat /mnt/var/backups/flash-kernel/mtd1 >/dev/mtdblock1
      cat /mnt/var/backups/flash-kernel/mtd2 >/dev/mtdblock2
  • recovery steps (if raid1 consists of /dev/sda3 and /dev/sdb3)
    • btrfs fi show
      displays whether both raid1 drives are accessible
    • echo 1 >/dev/block/sda/device/delete
      forces /dev/sda offline (e.g. in case of too many smart errors)
    • if btrfs fi show  displays that one drive is missing, e.g. sda3, do not run other btrfs commands to avoid errors which cause transition to ro filesystem, but do immediately run
      mount -o remount,degraded /dev/sdb3 /
    • attach replacement drive and check its device name with cat /proc/partitions (od dmesg), e.g sdc3
    • remove any existing btrfs data on replacement drive partition, e.g. on sdc3 by formatting it with ext4
      mkfs.ext4 -F /dev/sdc3
    • btrfs dev add -f /dev/sdc3 /
    • btrfs fi show
      • if sdc3 is shown twice, remove sdc3 with lower id from btrfs raid1
        btrfs dev del YOUR_DEVID /
      • if it is shown, that one drive is missing run
        btrfs del missing /
    • btrfs fi show
      this should know display two drives/partitions attached
    • to check for other error btrfs scrub might be run (time consuming)
    • reboot needed to remove option degraded from /proc/mounts

Switch hard disk with root filesystem

  • debian stretch on qnap sets kernel command line ROOT=”/dev/….” inside initramfs which is stored in flash. So using another hard disk requires to reflash initramfs
    • update-initramfs -u creates a new initramfs (at /boot/initrd.img-KERNEL_VERSION)
      and runs flash-kernel KERNEL_VERSION which creates /var/backups/flash-kernel/mtd2 (and mtd1) and flashes it
    • update-initramfs (/usr/share/initramfs-tools/hooks/flash_kernel_set_root) reads /etc/fstab to get the device with the root filesystem
    • use blkid YOUR_DEVICE_NAME to display the uuid of a block device
    • So to set a new root device, temporarily edit /etc/fstab (on the old root partition) to point to the new root filesystem device, run update-initramfs -u; then restore the old settings in/etc/fstab on old partition;
      verify that the new partition is correctly set in /etc/fstab on the new root partition,
    • additional step for recovery by tftp (based on instructions here)
      • backup flash partitions /dev/mtdblockN (N=0 … 5) to files mtdN
      • download installer kernel and initrd (reference)
        to determine kernel version (6281 or 6282)
      • pad kernel
        dd if=kernel-628X of=kernel.pad ibs=2097152 conv=sync (with X=1 or 2)
      • create tftp img file
        cat mtd0 mtd4 mtd5 kernel.pad initrd mtd3 > F_TS-219_di
        and copy this recovery image file to another computer or storage device
    • finally reboot
    • if reboot fails, load qnap recovery live cd iso here
      • run live cd in e.g. virtualbox (use a network adapter not connected to existing lan)
      • copy recovery image file to /tftpboot/ on live cd
        • add a second network interface connected to local lan to allow upload by ssh
        • sudo su
        • ifconfig eth1 YOUR_LAN_IP
        • set a password for user ubuntu
          passwd ubuntu
        • upload img file with scp to /home/ubuntu
        • ifconfig eth1 down (because dhcp server of live cd)
        • cp img file to /tftpboot/ and replace existing img file for your qnap device
      • power off qnap and power on with reset button pressed (until double beep):
        this should reflash qnap flash partitions with debian installer


Example btrfs send, btrfs receive (btrfs volumes mounted at /backup and at /backup2;
transfer readonly subvolume rootf_ro from volume mounted at /backup to other volume mounted at /backup2)

  • btrfs sub snapshot -r /backup/rootfs /backup/rootfs_ro

  • btrfs send /backup/rootfs_ro |btrfs receive /backup2

Resize/shrink btrfs partition with root filesystem (e.g. openmediavault needs separate data partition);
assume that btrfs partition is mounted at /backup using /dev/sda2

  • btrfs filesystem resize 32G /backup
  • fdisk /dev/sda
    • p
    • d 2
    • n 2 default start +40G
      do not delete btrfs signature
    • p
    • w
    • q
  • partprobe
  • btrfs filesystem resize max /backup
  • btrfs filesystem show
  • cat /etc/fstab

Add openmediavault (version 4.x arrakis for debian stretch): instructions

  • echo “deb arrakis main” > /etc/apt/sources.list.d/openmediavault.list
  • apt-get install openmediavault-keyring
  • apt-get update
  • apt-get install openmediavault
  • omv-initsystem

Create raid0 btrfs volume and use subvolumes as shared folders:

  • mkfs.btrfs -L datafs -d raid0 /dev/sda4 /dev/sdb4
  • then use webinterface filesystems to mount this volume
    (gets mounted at /srv/dev-disk-by-label-datafs; cat /etc/fstab)
  • btrfs subvol create /srv/dev-disk-by-label-datafs/YourShare
  • then use webinterface to define shared folder YourShare
    • use shared folder / ACL if write access fails
  • (in case of macos sierra don’t) share this folder by nfs
    • currently, 2017-11-02, apply changes fails
      (tries to mount second partition included in btrfs raid0)
    • reboot from console
    • log into webinterface and apply change again: should work
    • nfs://your_ip/export/YourShare/
      (with default settings needs option insecure)
    • currently, 2017-11-02, nfs with macos sierra is awfully slow but samba sharing (activate wins server) works
      • nfs seems to have locking issues because ejecting share from macos finder fails (unless finder is forced to restart)

minidlna media player

  • apt-get install minidlna
  • btrfs subvol create /srv/dev-disk-by-label-datafs/Musik
  • omv webinterface: add shared folder Musik on device with datafs
    which creates /sharedfolders/Musik
  • edit /etc/minidlna.conf (compare with this reference)
    • inotify=no
    • friendly_name=YOUR_MEDIA_SERVER
    • media_dir=A,/sharedfolders/Musik
  • chown -R minidlna:minidlna /sharedfolders/Musik
  • create media file index from scratch
    • systemctl stop minidlna
    • rm /var/cache/minidlna/*
    • systemctl start minidlna
  • if new mediafiles have been added
    • chown -R minidlna:minidlna
    • systemctl restart minidlna
  • if minidlna does not get discovered by plugplayer (ios), then manually add server:
  • to display status of minidlna use a webbrowser:


  • download deb from here
  • upload this file from omv webinterface section plugins
  • install plugin openmediavault-omvextrasorg
  • settings / system / OMV-Extras: activate wanted repository
  • check (again) for available plugins (or apt-get update)

usage: some devices on internal network send diagnostic emails; keep those emails in internal network by setting up a smtp server which delivers emails directly to existing dovecot mail server using lmtp.

install postfix on qnap running dovecot

addgroup postfix
adduser -D -H -G postfix postfix
addgroup postdrop

export PATH=/opt/bin:/opt/sbin:$PATH
ln -s /opt/include /usr/include
cd /opt/src
wget –no-check-certificate
tar -xzf postfix-2.11.11.tar.gz
cd postfix-2.11.11

export CCARGS=’-I/opt/include -L/opt/lib -DDEF_COMMAND_DIR=\”/opt/sbin\” \
-I/opt/include/sasl -DUSE_SASL_AUTH -DDEF_SERVER_SASL_TYPE=\”dovecot\” \
-DHAS_SSL -I/opt/include/openssl -DUSE_TLS\
-DDEF_CONFIG_DIR=\”/opt/etc/postfix\” -DDEF_DAEMON_DIR=\”/opt/libexec/postfix\” -DDEF_DATA_DIR=\”/opt/var/lib/postfix\” \
-DDEF_MAILQ_PATH=\”/usr/bin/mailq\” -DDEF_HTML_DIR=\”/opt/share/doc/postfix/html\” -DDEF_MANPAGE_DIR=\”/opt/man\” \
-DDEF_NEWALIAS_PATH=\”/opt/bin/newaliases\” -DDEF_QUEUE_DIR=\”/opt/var/spool/postfix\” \
-DDEF_README_DIR=\”/opt/share/doc/postfix/readme\” -DDEF_SENDMAIL_PATH=\”/opt/sbin/sendmail\”‘

export AUXLIBS=’-lcrypto -lssl’

export LD_LIBRARY_PATH=/opt/lib
(else postconf, called by post-install, does not find libdb)

make tidy

replace #!/bin/sh by #!/opt/bin/bash in makedefs and post-install

edit post-install: search for chown
– replace chown root by chown admin
– in case of chown $owner (followed by chgrp $group) add these lines above the line with chown (at 2 places)
case $owner in root) owner=admin;; esac
case $group in root) group=administrators;; esac

make install

edit scripts:
replace #!/bin/sh by #!/opt/bin/bash
and add below
export PATH=/opt/bin:/opt/sbin:$PATH
export LD_LIBRARY_PATH=/opt/lib

postfix requires a domainname:

  • either workaround: so set in /etc/hosts of mail clients myserver myserver.local
    if hostname of the mailserver is myserver

    • set in /opt/etc/postfix/
      myhostname = myserver.local
      mydestination = myserver, myserver.local, localhost
      mynetworks =
  • or better: if you own mydomain.tld and if you have access to dns settings
    • create A record: mail.internal.mydomain.tld
    • create MX record: internal.mydomain.tld pointing to mail.internal.mydomain.tld
    • set in /opt/etc/postfix/
      myhostname = mail.internal.mydomain.tld
      mydestination = internal.mydomain.tld, myserver, myserver.local, localhost
      mynetworks =
    • use qnap web admin interface to create a normal user myname
      mailaddress is then myname@internal.mydomain.tld
      computers on can send mails by smtp without authentication
      using mailserver mail.internal.mydomain.tld

for debugging: postfix logs to syslogd which does not run by default on qnap

  • start syslogd: syslogd
    display messages with: tail -f /var/log/messages
    when finished: killall syslogd
  • increase verbosity of postfix by editing /opt/libexec/postfix
    replace master -w by master -vvv -w
  • restart postfix:
    postfix stop
    postfix start

connect by lmtp with dovecot for non virtual user setup
mailbox_transport = lmtp:unix:private/dovecot-lmtp (in

using /opt/var/spool/postfix/private/auth
and /opt/var/spool/postfix/private/dovecot-lmtp

after everything works non existing users can be rejected by postfix (
smtpd_recipient_restrictions = reject_unverified_recipient

main config: service lmtp has to be enabled
if sasl auth is configured port 587 udp and tcp has to be added to etc services!
submission 587/tcp
submission 587/udp

so add to postfix start script
cat /etc/services |grep -q “[^0-9]587/tcp” || echo “submission 587/tcp” >>/etc/services
cat /etc/services |grep -q “[^0-9]587/udp” || echo “submission 587/udp” >>/etc/services
ln -s /opt/lib/ /lib
(last line because LD_LIBRARY_PATH=/opt/lib does not work for every subprocess of postfix)

problem when using dovecot with simple unix system users in default config:
postfix gives mail_user@mail_domain to lmtp but dovecot passdb of type shadow
and userdb of type passwd want mail_user (without @mail_domain suffix)

workaround: switch to passwd-file type of db for passdb and for userdb
which allows with args = username_format=%n to skip @mail_domain
Set in /opt/etc/dovecot/conf.d/auth-system.conf.ext:
service auth {
user = $default_internal_user
group = administrators
service auth-worker {
user = $default_internal_user
group = administrators

passdb {
driver = passwd-file
args = scheme=md5-crypt username_format=%n /etc/shadow
userdb {
driver = passwd-file
args = username_format=%n /etc/passwd

service auth {
unix_listener /opt/var/spool/postfix/private/auth {
mode = 0660
user = postfix
group = postfix

result: mails from local network can be sent to qnap users using smtp on port 25 without authentication

todo configure certs for tls; test smtp(s) auth

Debian Edu, that is skolelinux, aims to make the life of admins comfortable. Users, attached computers and more (stored by openldap) can be administrated by included gosa gui.

But trying to update the main server from debian jessie to debian stretch (at last 2017-08) broke gosa: Error while connecting to LDAP: Could not bind to cn=gosa-admin,ou=ldap-access,dc=skole,dc=skolelinux,dc=no (while operating on LDAP server ldaps://ldap.intern)

Because this system has been updated multiple times, the auto generated gosa ldap password was not available. And the existing hashes of the password did not work with debian stretch.

Installing updates one year later (2018-07) did not solve the access error. So it was time to dive into ldap authentication of gosa and skolelinux.

Step 1: The program slapcat allows to export the whole ldap database to a ldif file and does not require a password: export.ldif

Step 2: Edit export.ldif and replace the gosa-admin password:

  • As ldap novice I had to learn that this password has to be encrypted with slappasswd and gets stored in base64 format:
    echo “$(slappasswd)” |openssl base64
    (just enter the new password, eg. toptopsecret, twice, when asked)
  • Search for gosa-admin in export.ldif and replace the text after userPassword:: by the output generated by the command described above
  • Stop slapd (systemctl stop slapd), move /var/lib/ldap to /var/lib/ldap.orig, create /var/lib/ldap and copy DB_CONFIG from ldap.orig to ldap
  • Import the edited export.ldif file and fix ownership:
    slapadd -l export.ldif
    chown openldap:openldap /var/lib/ldap
  • Start slapd:
    systemctl start slapd
    and in case of errors
    systemctl status slapd
    journalctl -f -u slapd (maybe, set loglevel in /etc/ldap/slapd.conf from none to 65535)

Note: Step 2 might be used to migrate a skolelinux configuration from one server to another

Step 3: Add the new password as cleartext to gosa.conf (in /etc/gosa/):

  • Create backup copies of gosa.conf and gosa.secrets
  • Edit gosa.secrets so that it is an empty file
  • Edit gosa.conf and search for adminPassword and set the clear text password
    (twice: at snapshotAdminPassword and at adminPassword)
  • Restart webserver (because /etc/gosa/gosa.secrets gets included into apache config)
    apache2ctl graceful
  • Try login at https://yourip/gosa
  • If login is successful create again backup copies of gosa.conf and gosa.secrets

Step 4: Encrypt passwords in gosa.conf  with gosa-encrypt-passwords tool:

  • Remove /etc/gosa/gosa.secrets (after having made backups of gosa.secrets and gosa.conf)
  • Run gosa-encrypt-passwords
  • If successful restart webserver
    apache2ctl graceful
  • Try login at https://yourip/gosa


Looking for a simple web based app to take notes I discovered and a fork which added markdown tagging and import/export:

Installation on debian stretch using apache2 as proxy allowing password protected access by ssl (described here and here):

  • apt-get install nodejs npm redis-server

  • mkdir -p /opt/nodejs
    cd /opt/nodejs
  • adduser –no-create-home –home /opt/nodejs/scrumblr –disabled-login –gecos “Scrumblr” scrumblr

  • git clone

  • chown scrumblr: -R /var/www/scrumblr
    cd scrumblr

  • npm install
  • add scrumbler extensions of ldidry and test scrumblr on the console:
    • su scrumblr -s /bin/bash

    • git remote add fork git fetch fork git pull fork master
    • node server.js –port 4242 –baseurl /your_url_dir
      bugfix (“RangeError…”): edit config.js and change the line redis: …
      redis: argv.redis || ‘redis://’
  • netstat -ant reveals that scrumbler listens on all interfaces; so replace in server.js line server.listen(conf.port);
    server.listen(conf.port, ‘’);
  • add a service description to /etc/systemd/system/scrumblr.service (reference) and enable scrumblr.service
    (and include startup argument  –baseurl /your_url_dir)
  • configure apache2 as proxy
    • enable modules: a2enmod proxy; a2enmod proxy_http
    • add a location section to virtual host config file in /etc/apache2/sites-available/
      <Location /your_url_dir>
    • apache2ctl configtest; apache2ctl graceful
  • Open http(s)://your_server.tld/your_url_dir/
    • mini bug: the link to demo board is an absolute url and thus ignores proxy url; to fix this remove absolute path in scrumblr/views/home.jade at line p.home!=…
      p.home!= ‘<a href=”demo”>’ + ‘demo</a>’
    • here is a reference for the use of markdown syntax (e.g. insert links and images)
  • Todo: properly support editing on android and ios devices
    • ios recognizes doubleclick but cursor cannot be moved
    • android does not recognize doubleclick
    • scrumblr/client/script.js line card.children(‘.content’).editable…: if event: ‘dblclick’ gets replaced by
      event: ‘click’
      enables editing empty cards on mobile devices at the price that on the desktop dragging of a card activates edit mode
    • differentiate between ‘click’ for touch devices and ‘dblclick’ for other devices: content of diff file is here.


  • install file server role: file management from other machine using \\servername\c$
    Import-Module Servermanager
    get-windowsfeature *
    add-windowsfeature fs-fileserver
  • blue console sconfig.cmd offers only Log Off or Shut Down / Restart.
    But pressing ctrl+alt+del offers Lock to lock the screen
  • install corefig to get some graphical management tools (docs here)
    set powershell to remote signed and unblock corefig ps* files:
    Set-ExecutionPolicy -ExecutionPolicy RemoteSigned
    Unblock-File -Path path_to_corefig\*.ps*
  • to open ports run powershell command
    New-NetFirewallRule -protocol tcp -localport 3551 -direction inbound -action allow -displayname apcupsd
    (rule is gets removed by Remove-NetFirewallRulle -displayname apcupsd)
  • to forward ports to another host run netsh command
    netsh interface portproxy add v4tov4 listenport=1234 listenaddress= connectport=5678 connectaddress=
    (netsh interface portproxy delete v4tov4 listenport=1234 listenaddress=
  • to display id of a vm use powershell (reference):
    $vm=get-vm -name your_vm_name
  • hyperv vm’s can be managed by 5nine Manager (free edition for up to 6(? only seen 2) local vm’s)
    or use ProHVM by (Standard edition is free; key file by email after registration; for multiple servers multiple key files can be obtained; works with local and remote hosts!)
  • this tool runs on hyper v server and includes a vm console
    (which may be put into HKLU/…/Run; fetch cmd args using process explorer)
  • to install drivers from inf files use
    pnputil -i -a path_to_inf_file.inf
  • some server 2012 core specific help for powershell is here

Server 2008r2 sp1 as guest vm:

  • easily moved from hard disk to vhdx by running disk2vhd tool inside physical 2008r2 server
    with a network share as target
  • important, if server 2008r2 includes hyper v role: bluescreen when hyper v 2012 guest tools are installed:
    Boot 2008r2 inside vm; use server manager to uninstall hyper-v role (needs 2 or more reboots); if server manager confirms successful removal of hyper v role, then install 2012 hyper v guest tools; insert hyperv guest iso using hyper v manager (5nine).

Special note for mainboard with adaptec softraid for onboard ata disks

  • server 2012r2 can be installed on such a raid drive, if sata raid driver is installed from usb during installation (e.g for amd boards with sp5100 chip)
  • adaptec storage manager runs inside hyper v 2012r2; email notifications can be configured; manual.
    (smtp access by ssl/tls via stunnel; stunnel -install configures stunnel as auto starting service; config: client=yes accept= connect=yourmailserver.tld:465)
  • smartctl of smartmontools seems to be unable to look into physical drives of this adaptec softraid devices (but possible with intel softraid)


First install composer.

  • dependencies: curl and git
  • download and verify composer-setup.php as described at composer homepage section download:
  • install as /usr/local/bin/composer: php composer-setup.php –install-dir=/usr/local/bin –filename=composer

Second install yii as described here:

  • create an installation directory for the new yii project one level above document root, e.g. mystuff../
  • run composer inside directory mystuff:
    • composer global require “fxp/composer-asset-plugin:^1.3.1”
    • composer create-project –prefer-dist yiisoft/yii2-app-basic ./
    • If document root is defined as public_html ,and should be handled by yii framework, then run:
      ln -s yii/web/ public_html

If a database backend is used, yii code to handle tables can be auto generated using yii component gii.

  • configure config/web.php according to manual:
  • ensure that the web server has write (at least temporary) access to yii directory (chown -R www-data:www-data yii)
  • create the database table and add comments to each table field (which will become labels for table edit form fields)
  • create Model and CRUD using gii
  • uncomment primary index field id in views/your_table_name/index.php

To create pdf output use plugin yii-mpdf:

  • install plugin: composer require kartik-v/yii2-mpdf “1.0.1”
  • add pdf config to components array in config/web.pdf
    (and do not forget to add at the beginning of web.php: use kartik\mpdf\Pdf;)
  • for a view file views/your_table_name/view2.php add to controllers/yourTableNameController.php
    $pdf = Yii::$app->pdf;
    $pdf->content = $this->renderPartial(‘view2’, [‘model’ => $this->findModel($id)]);
    return $pdf->render();
  • to change formatting in dataset detail view
    • reference is source code: vendor/yiisoft/yii2/widgets/DetailView.php (and vendor/yiisoft/yii2/base/Widget.php):
      variables $template = ‘<tr><th{captionOptions}>{label}</th><td{contentOptions}>{value}</td></tr>’
      and $options = [‘class’ => ‘table table-striped table-bordered detail-view’]
    • thus add in file views/your_table_name/view2.php:
      DetailView::widget([ ‘model’ => $model, ‘template’ => ‘your_settings’,  ‘options’ => [your_settings], …

User authentication:

(Plugin which allows user registration with email confirmation etc.:–cms-22974)

  • the standard base template of yii includes user authentication with hardcoded passwords in file
  • some configuration is set in config/web.php: array components, sub array user, e.g. enableAutoLogin might be set to false
  • views/site/login.php defines the login page, e.g. remember me might be removed
  • example code to get name of logged in user:
    use app\models\User;
    if( !(Yii::$app->user->identity===null) ){echo User::findIdentity(Yii::$app->user->id)->username;} else {echo “guest”;}
  • if( !(Yii::$app->user->identity===null) && ‘100’===Yii::$app->user->id){echo “is admin”;}

Configure Mailer

  • set admin email address in config/params.php
  • configure mailer in config/web.php as described in–cms-22974
  • edit contact form views/site/contact.php

Using a scanner often results in large files. OS X preview program allows to export to multiple formats. Choosing filetype pdf enables the option to apply quartz filters (generic export dialog; shortcut export to pdf does not show quartz filters in OS X 10.11.6). The builtin quartz filter reduce file size does create tiny documents but text might get unreadable.

But the builtin tool ColorSync allows to modify and create quartz filters (german howto with screenshots here). If a newly created filter should show up in the export dialog of the preview program it has to be copied from
/Users/your_name/Library/Filters to /Library/PDF Services
(tested in OS X 10.11.6).

Example of settings for small but (rather) readable pdf files:

  • Image: pixel per inch = 100; quality = high; all other settings empty
  • Image (gray): pixel per inch = 100; quality = high; all other settings empty
  • Image compression: jpeg; quality = slider one tick below medium position

To shrink multiple pdf files the custom quartz filter can be used from the command line:

  • Open Tools / Automator and create a new workflow
  • add action pdf / apply quartz filter
  • do not add other actions
  • save this workflow, e.g. as /yourpath/pdfreduce
  • copy all pdf files which should be converted to a new folder
  • open a terminal and cd to the folder with pdf files which should be shrinked
  • to convert one file run: automator -i yourdoc.pdf /yourpath/pdfreduce.workflow
  • multiple files: for f in *.pdf; do echo “$f”; automator -i “$f” pdfreduce.workflow; done