23.01.2022
Force SSH to use IPv6
In situations where IPv6 connectivity performs better than IPv4, you might want to force SSH to use IPv6. In interactive mode this can be achieved with the -6 commandline parameter.
But in situations where you can't modify the commandline parameters a different approach is needed (for example in rsync backup scripts which use SSH as underlying transport layer).
We can use the ssh_config file to encforce that IPv6 is used for a specific host:
Host myipv6host
AddressFamily inet6
This instructs all SSH commands to use IPv6 when connecting to myipv6host.
The same approach also works to force usage of Legacy IP by specyfing inet as address family.
10:53 | Networking | Permalink
19.01.2022
Google Analytics removed
After running it for a bit more than a decade, I've now removed again the Google Analytics tracking from this site. It does not feel appropriate anymore on a personal website.
At the moment no alternative statistics solution is in place yet, but I could imagine setting up a self-hosted solution like Matomo or Plausible in the future.
22:45 | Webdesign | Permalink
05.01.2022
Wordle
Wordle seems to be the trending topic these days.
It's a word game similar to the french Motus game show (resp. the american Lingo game show).
Wordle 200 4/6
⬜⬜⬜🟩⬜
⬜⬜🟨🟩⬜
⬜⬜⬜🟩🟩
🟩🟩🟩🟩🟩
07:09 | Misc | Permalink
01.01.2022
Y2K22
Turns out that signed 32-bit numbers can be exhausted long before Y2038, when you use them to store time in YYMMDDHHMM format. (via)
21:48 | Coding | Permalink
19.04.2021
Open Source on Mars
Received a badge from GitHub's Open Source on Mars initiative :-)
16:21 | Coding | Permalink
28.03.2021
security.txt
This website now also serves a security.txt file which is a standardized way of making security contact information available. (Wikipedia)
The file is available in two locations /security.txt (the classic location) and /.well-known/security.txt (the standard location following RFC8615).
To easily add the file on all my domains, I'm using the following nginx config snippet.
location /security.txt {
add_header Content-Type 'text/plain';
add_header Cache-Control 'no-cache, no-store, must-revalidate';
add_header Pragma 'no-cache';
add_header Expires '0';
add_header Vary '*';
return 200 "Contact: mailto:andreas+security@jaggi.info\nExpires: Tue, 19 Jan 2038 03:14:07 +0000\nEncryption: http://andreas-jaggi.ch/A3A54203.asc\n";
}
location /.well-known/security.txt {
add_header Content-Type 'text/plain';
add_header Cache-Control 'no-cache, no-store, must-revalidate';
add_header Pragma 'no-cache';
add_header Expires '0';
add_header Vary '*';
return 200 "Contact: mailto:andreas+security@jaggi.info\nExpires: Tue, 19 Jan 2038 03:14:07 +0000\nEncryption: http://andreas-jaggi.ch/A3A54203.asc\n";
}
This snippet is stored in a dedicated file (/etc/nginx/conf_includes/securitytxt) and is included in the various server config blocks like this:
server {
server_name example.com;
include /etc/nginx/conf_includes/securitytxt;
location / {
# rest of website
}
}
08:16 | Webdesign | Permalink
13.02.2021
Fixing 'snmpd[19784]: error on subcontainer 'ia_addr' insert (-1)' messages
The default configuration of snmpd on Debian has debug level logging enabled and thus we end up with a constant flood of these messages in /var/log/syslog
snmpd[19784]: error on subcontainer 'ia_addr' insert (-1)
The fix is to lower the logging level, which can be accomplished like this on systems with systemd:
cp /lib/systemd/system/snmpd.service /etc/systemd/system/snmpd.service
sed -i 's/Lsd/LS6d/' /etc/systemd/system/snmpd.service
systemctl daemon-reload
systemctl restart snmpd
On systems without systemd, the logging level is set by the init script (unless explicitly configured in /etc/default/snmpd), and can be changed like this:
sed -i 's/Lsd/LS6d/g' /etc/default/snmpd
sed -i 's/Lsd/LS6d/g' /etc/init.d/snmpd
service snmpd restart
08:57 | Linux | Permalink
04.02.2021
Embracing the future with SolNet
This was the initial state of my new SolNet fibre connection:
As I am a proponent of IPv6 this made me very happy, but unfortunately about 20% of my daily websites only offer legacy Internet (which later on I got working as well).
10:01 | Networking | Permalink
