, 3 min read
I am running fail2ban since November 2017 and all unsuccessful attempts to log-in to sshd are monitored. Breaking down these attempts according country shows that Chinese IP addresses are coming first here. The numbers are: 27639 China 13589 United States 8641 France 3985 India 3418 …
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Recently one node was changed from octacore to hexacore. Since that time sinfo showed this node in STATE drain. Stopping and restarting slurmctld did not resolve the issue. Log file /var/log/slurm-llnl/slurmctld.log showed [2019-12-31T23:57:52.588] error: Node X appears to have a different…
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When using bitmap indexes in Oracle database one must watch out for deadlocks, see for example Tom Kyte's remark on Bitmap indexes and locking. This is by design of bitmap indexes. Below example is given in Oracle Bitmap Indexes Limitations/Restrictions. Problem occurs on "Oracle Database 12c…
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Dynu is a free dynamic DNS service. As described in Microsoft Brought Down No-IP.org I have to cope with big business just pushing their own interest and not caring on small business or private customers. I tried to update IP address for Dynu using ddclient using package ddclient. This failed. The…
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This blog was viewed more than 90.000 times since its inception and had more than 68.630 visitors. The averages per month are: The most popular posts over one year are: The most popular posts over all years are: USA is at the top of viewers of my blog this year, as before:
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Google Chrome on Android version 74.0.3729 can no longer clear history, cookies, local data, etc. See screenshot below. Even when this process is running completely uninterrupted, nothing happens. I.e., changing display sleep time to 30 minutes, Google Chrome will not finish. Problem solution:…
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If one needs to know when some website has been visited in Mozilla Firefox then go to the default directory and open the places.sqlite file: cd ~/.mozilla/firefox/<xyz>.default/ sqlite3 places.sqlite Issue below SQL command select visit_date, datetime(visit_date/1000000,…
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On 04-Mar-2019 I shortly experienced a downtime of my two blogs here on WordPress.com. Just a few minutes. Because this is so rare I made a screenshot of this event. See below. Below two blogs were affected: Elmar Klausmeier's Weblog Collected Links
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I encountered the following error, when I wanted to connect to Oracle v12.2.0.1.0 database with Java 1.8.0_192-b26: java.sql.SQLRecoverableException: IO Error: Connection reset by peer, Authentication lapse 321631 ms. This was unexpected as the same program did run absolutely fine on another Linux…
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I had to provide access to an Oracle database but the standard port at 1521 was hindered by company firewall and company proxy rules. In previous times there was iSQL*Plus, but this product no longer seems to be available. I found Adminer as an alternative. It is written by Jakub Vrána. It is very…
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This blog was viewed more than 80.200 times since its inception and had more than 60.000 visitors. The averages per month are: Between 1,000 and 2,000 views per month in bar chart form: The most popular posts over all years are: The most popular blog posts this year were: USA is at the top of…
, 19 min read
In Using Odroid as IP Router I wrote about using my Odroid as router and firewall. Additionally I inspect who tries to log-in to my machines using the lastb command. Sample output is below: $ lastb admin ssh:notty 202.166.220.10 Mon Oct 1 09:51 - 09:51 (00:00) admin ssh:notty …
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Java Nashorn is the JavaScript engine shipped since Java 8. You can therefore use JavaScript wherever you have at least Java 8. Java 8 also has a standalone interpreter, called jjs. It is possible to create a Java HashMap and use this structure directly in JavaScript. Here is the code: import…
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This blog was viewed more than 71.400 times since its inception and had more than 54.000 visitors. The averages per month are: Between 1,000 and 2,000 views per month in bar chart form: The most popular blog posts over all years are: The most popular blog posts this year were:
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Had an issue with update of ARM ArchLinux which I use here. Error messages like: (95/95) checking keys in keyring [####################################################] 100% (95/95) checking package integrity …
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Beyond Compare is a graphical file comparison tool sold by Scooter Software. Its open-source competitors are mainly vimdiff, and kdiff3. Its advantage is ease-of-use. While comparing files they can be edited instantly. You can diff complete directory trees. It is written in Delphi Object Pascal,…
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One can use the instant messaging client Pidgin and Skype. Skype for Business was previously called Lync. Install Pidgin pacman -S pidgin and install the SIP/Simple protocol for Skype for Business/Office 365/Lync pacman -S pidgin-sipe Setting up the account: Use your company mail-address.…
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1. Problem statement. You have an encrypted disk and want to decrypt the disk during boot while not sitting in front of your computer. Solution is sketched and indicated in dm-crypt/Specialties. Below is a little bit more explanation. For the following you must be root. 2. Required software…
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Google announced that starting with Chrome version 68 they will gradually mark HTTP-connections as "not secure". "Let's Encrypt" is a free service for web-masters to obtain certificates in an easy manner. Work on "Let's Encrypt" started in 2014. Setting up "Let's…
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I stumbled upon Hiawatha web-server when I read about a web-server for a houseboat by Ronald Scheckelhoff, WB8LZR. I had used Apache, thttpd, Lighttp, NGINX, and others before. Now I use the Hiawatha web-server. Since August 2023 I use the NGINX web-server. Hiawatha has three objectives, which are…