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Convert .pdf to .ics

rostoics_mainThis tool converts NetLine/Crew CrewLink roster .pdf files into .ics calendar files.


Please read these Instructions carefully prior using this tool !!!



1a. Download your roster using your company's web interface (NetLine/Crew CrewLink).
1b. Download your roster using the CrewLink App.
2. Save the roster locally as .pdf file.
3. Go to Convert .pdf to .ics.
4. Press Browse... button and select the just downloaded .pdf file.
5. Press Upload roster (.pdf file). Roster is then processed by rostoics tool.
6. Press Download roster (.ics file) and save that file locally.
7. Import the .ics file into your calendar using your preferred gateway.

Select roster (.pdf file) to be uploaded:

(wait 5-10 seconds for roster processing to finish)

rsync backup from Ubuntu server to Synology NAS

This tutorial describes how to do scripted passwordless encrypted automatic rsync backups from an Ubuntu server to a Synology NAS. It is supposed to be a general guide, which can be used with other Linux variants as well. Only minor changes should be required.

I did this first of all in order to help other Synology NAS users perform efficient and secure backups to their NAS, but also to get get my scratch pad like personal installation notes in a more reasonable shape, so I can recall later on myself what I did, how, and why.

Synology NAS shell – Basics

synology_dsmThe following article describes some basics regarding first contact with Synology DSM shell.

I used DSM 6.1.3 out of the box, running in a Virtual machine (using Virtual Machine Manager) on DS1817+ hardware.

Null client Postfix setup

The following setup describes a postix setup to send e-mails using an existing SMTP server. It is not designed to receive e-mails. My provider is DreamHost, but setup should be very similar with other hosters. I used a VM with the Ubuntu Server 16.04.1 out of the box installtion (ubuntu-16.04.1-server-amd64). This VM has no real FQDN, hence an imaginary needs to be configured in order to make the SMPT server accept sent e-mails.

Video tutorials

Below you see a QAD (quick and dirty) screenshot video tuorial which shows how to convert a roster using the www method. Screenshots taken on iPhone 6S (iOS 11.2.6). rostics 1.0.18-PL2 was used.

DNS Stock update script

dnsstock_update_screenshotThis script updates the DNS records of DNS Stock.

It generates an URL<domain>&username=<username>&password=<pass>&myip=<ipaddr>, which is eventually passed to the DNS Stock server. The code is basically about parsing, validating, checking and formatting the returned WAN IP <ipaddr>. Two URLs are configured to check WAN IP. If the first one returns an error, the second one is queried. If that one fails as well, the script abandons. The logfile dnsstock_update.log reveals relevant details about what happened.

Configured passwords can either be plain text (depreciated) or MD5 crypted (preferred), as visible on DNS Stock site. The DNS Stock server accepts both formats.

Code and logfile entries should be self-explanatory.


Comments are desired.


.htaccess rewrite of directory to new domain

Online files stored on a web server have, most of the time, many references pointing to these files.

In my case, my web hoster decided that I had to take away files stored in a folder called downloads. However many links from my phpbb3 forum pointed to that directory. Needless to say, that this would require a lot of manual work adjust all these links.

Logitech Media Server for Squeezebox on Ubuntu Server 12.04.5

Logitech Media Server (formerly SlimServer, SqueezeCenter and Squeezebox Server) is a streaming audio server supported by Logitech (formerly Slim Devices), developed in particular to support their Squeezebox range of digital audio receivers. The following post describes how to install Logitech Media Server for Squeezebox on Ubuntu Server 12.04.5.

Move Ubuntu 14.04 Desktop ESP partition

The following article describes how Ubuntu 14.04 is installed on the same HDD having Windows 7 already installed, Ubuntu 14.04 using use a separate ESP partition.

Check RapidCRC (Windows) md5 checksum files using md5sum (Unix)

I use RapidCRC Unicode (0.3.11) for Windows to generate md5 checksum files for various source files, mainly huge video footage, but it can be anything of course. Footage files, since large, can easily be subject to data rot due age or other electromagnetic effects influencing data consistency. RapidCRC can also be used to check data integrity – this works flawlessly. But as soon as the footage file including md5 checksum file is copied to a Unix system, md5 checksum checks get complicated since the Unix md5sum command doesn’t cope very well with RapidCRC created checksum files. The reason for this is that Windows uses CR (carriage return, 0x0d) followed by LF (line feed, 0x0a) to terminate a line while Ubuntu only uses LF (line feed, 0x0a). No big deal, but md5sum simply doesn’t cope with (see below).

Despite that the fact that md5 states that the generated checksum file is md5sum compatible, this doesn’t seem to be the case.


This is a RapidCRC generated md5 checksum file (text and hex code).
Notice the 0x0d and 0x0d at the end of the (only) line.

root@ganymede:/media/raid-main/# transfer# cat "movie 1.mpg rapidcrc.md5"
f724a9b3aa7ab2efdf8528daff90a400 *movie 1.mpg
root@ganymede:/media/raid-main/# transfer# xxd -c16 -a "movie 1.mpg rapidcrc.md5"
0000000: 6637 3234 6139 6233 6161 3761 6232 6566  f724a9b3aa7ab2ef
0000010: 6466 3835 3238 6461 6666 3930 6134 3030  df8528daff90a400
0000020: 202a 6d6f 7669 6520 312e 6d70 670d 0a     *movie 1.mpg..

Now the md5sum details (text and hex code).
Notice the 0x0a at the end of the (only) line.

root@ganymede:/media/raid-main/# transfer# cat "movie 1.mpg md5sum.md5"
f724a9b3aa7ab2efdf8528daff90a400  movie 1.mpg
root@ganymede:/media/raid-main/# transfer# xxd -c16 -a "movie 1.mpg md5sum.md5"
0000000: 6637 3234 6139 6233 6161 3761 6232 6566  f724a9b3aa7ab2ef
0000010: 6466 3835 3238 6461 6666 3930 6134 3030  df8528daff90a400
0000020: 2020 6d6f 7669 6520 312e 6d70 670a         movie 1.mpg.

Apart from the above mentioned line termination, an * in front of the source file name is also a difference. However this doesn’t seem to disturb md5sum.

The test directory shows the source file itself, the RapidCRC generated md5 checksum file and, for movie 1.mpg only, the md5sum created md5 checksum file.

root@ganymede:/media/raid-main/# transfer# ls -l
total 28
-rw-r--r-- 1 root root 22 May  2 23:15 movie 1.mpg
-rw-r--r-- 1 root root 47 May  2 23:17 movie 1.mpg rapidcrc.md5
-rw-r--r-- 1 root root 46 May  2 23:42 movie 1.mpg md5sum.md5
-rw-r--r-- 1 root root 33 May  2 23:15 movie 2.mpg
-rw-r--r-- 1 root root 47 May  2 23:17 movie 2.mpg rapidcrc.md5
-rw-r--r-- 1 root root 31 May  2 23:16 movie 3.mpg
-rw-r--r-- 1 root root 47 May  2 23:17 movie 3.mpg rapidcrc.md5

Now … if md5sum is applied to the RapidCRC md5 checksum file, an error shows. The md5sum md5 checksum file is accepted without errors.

root@ganymede:/media/raid-main/# transfer# md5sum -c "movie 1.mpg rapidcrc.md5"
: No such file or directory
: FAILED open or read
md5sum: WARNING: 1 listed file could not be read
root@ganymede:/media/raid-main/# transfer# md5sum -c "movie 1.mpg md5sum.md5"
movie 1.mpg: OK

The following sed command parses the directory for md5 checksum files, deletes the 0x0d and 0x0a at each line end which are replaced by a single 0x0a

root@ganymede:/media/raid-main/# transfer# sed -s '$s/\r$//' *.md5
f724a9b3aa7ab2efdf8528daff90a400  movie 1.mpg
f724a9b3aa7ab2efdf8528daff90a400 *movie 1.mpg
93adea3dc473dd7ae029d630050fd9b8 *movie 2.mpg
b56962d703c9de6bf87f8bcc69614e6a *movie 3.mpg
root@ganymede:/media/raid-main/# transfer# sed -s '$s/\r$//' *.md5 > output
root@ganymede:/media/raid-main/# transfer# xxd -c16 -a output
0000000: 6637 3234 6139 6233 6161 3761 6232 6566  f724a9b3aa7ab2ef
0000010: 6466 3835 3238 6461 6666 3930 6134 3030  df8528daff90a400
0000020: 2020 6d6f 7669 6520 312e 6d70 670a 6637    movie 1.mpg.f7
0000030: 3234 6139 6233 6161 3761 6232 6566 6466  24a9b3aa7ab2efdf
0000040: 3835 3238 6461 6666 3930 6134 3030 202a  8528daff90a400 *
0000050: 6d6f 7669 6520 312e 6d70 670a 3933 6164  movie 1.mpg.93ad
0000060: 6561 3364 6334 3733 6464 3761 6530 3239  ea3dc473dd7ae029
0000070: 6436 3330 3035 3066 6439 6238 202a 6d6f  d630050fd9b8 *mo
0000080: 7669 6520 322e 6d70 670a 6235 3639 3632  vie 2.mpg.b56962
0000090: 6437 3033 6339 6465 3662 6638 3766 3862  d703c9de6bf87f8b
00000a0: 6363 3639 3631 3465 3661 202a 6d6f 7669  cc69614e6a *movi
00000b0: 6520 332e 6d70 670a                      e 3.mpg

If the stdout of sed command is piped to md5sum command, the RapidCRC md5 checksum files can be used to check data integrity.

root@ganymede:/media/raid-main# sed -s '$s/\r$//' *.md5 | md5sum -c
movie 1.mpg: OK
movie 1.mpg: OK
movie 2.mpg: OK
movie 3.mpg: OK
root@ganymede:/media/raid-main# sed -s '$s/\r$//' *.md5 | md5sum -c --quiet

String operations (ubuntu forums)
RapidCRC Unicode