Archive for the ‘Internet protocol suite’ Category
Posted by jpluimers on 2026/10/20
I have been using rsync for years now to sync directories around on VMware ESXi systems with great success.
Usually when upgrading to new physical machines, I synced the things to migrate to a big disk, then physically mounted that disk in a new machine.
Not this time: because of an unscheduled event I had to bring up the target machine in a different place before I could assemble the data on the big disk.
But since there was a network tunnel between the networks of both ESXi machines, I wanted to transfer over ssh: a thing I had done numerous times between various Linux and unix machines.
The cool thing is that rsync supports remote connections over ssh out of the box. Between ESXi machines, I bumped into this error though:
sh: rsync: not found
rsync: connection unexpectedly closed (0 bytes received so far) [Receiver]
rsync error: error in rsync protocol data stream (code 12) at io.c(226) [Receiver=3.1.2]
Command exited with non-zero status 12
The last three lines are collateral of the first line, which I queried [Wayback/Archive] “sh: rsync: not found” – Google Search. Further below I will go deeper into the rabbit-hole I took, but the actual solution was to Read the rest of this entry »
Posted in *nix, *nix-tools, ash/dash, ash/dash development, BusyBox, Development, ESXi6, ESXi6.5, ESXi6.7, man/manual pages, OpenSSH, Power User, rsync, Scripting, Software Development, SSH, ssh/sshd, Virtualization, VMware, VMware ESXi | Leave a Comment »
Posted by jpluimers on 2026/10/15
Some links on Supermicro IPMI SSL because of SSL_ERROR_UNSUPPORTED_VERSION which can either mean your SuperMicro motherboard is too old to include newer TLS versions (X9 series and older motherboards; first try to upgrade firmware and BIOS; check supported TLS with [Wayback/Archive] /bin/bash based SSL/TLS tester: testssl.sh), or you misconfigured custom TLS certificates.
Some links:
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Posted in Communications Development, Development, Hardware, Internet protocol suite, Mainboards, Power User, Software Development, SuperMicro, testssl.sh, TLS | Leave a Comment »
Posted by jpluimers on 2026/08/26
Likely what I want is not possible because of CORS or CSP (both security features, often mixed up in writings), but just in case below are some links I found.
The problem at hand was that I wanted to use the functionality of a site like [Wayback/Archive] Redirect Checker | Check your Statuscode 301 vs 302, but on the client side because sometimes redirects depend on locality (for example, but not limited to, AliExpress sites).
Thinks like these fail with CSP errors like Refused to connect to 'https://t.co/Ui4Wmesq1j' because it violates the following Content Security Policy directive: "connect-src chrome://resources chrome://theme 'self'".:
var xhr = new XMLHttpRequest();
xhr.onload = function() {
if (this.status < 400 && this.status >= 300) {
console.log('request redirects to ' + this.getResponseHeader("Location"));
} else {
console.log('request does not redirect');
}
}
xhr.open('HEAD', 'https://t.co/Ui4Wmesq1j', true);
xhr.send();
Links – many of them mentioning CORS, but few CSP:
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Posted in Communications Development, Development, HTTP, Internet protocol suite, Software Development, TCP, Web Development | Tagged: 1656, 2062, 763 | Leave a Comment »
Posted by jpluimers on 2026/04/15
Most of the links from my blog get accompanied with Wayback or Archive.today links, but some don’t.
For those, I need to find a broken/404 link checker which I already hinted at in scr.im « Share your email in a safe way. Get less spam.
Some links that hopefully help me:
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Posted in Development, HTTP, Internet protocol suite, Power User, Software Development, TCP, Web Development | Leave a Comment »
Posted by jpluimers on 2026/01/06
Everytime when installing a pfSense router from scratch, I seem to re-learn a few of the below quirks. So it was finally time to document them (:
Quite a few of my pfSense configurations are just doing routing between various networks, should not provide DHCP leases and do not always need or have a WAN connected (i.e. they are LAN-only).
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Posted in Communications Development, Conference Topics, Conferences, Cyberchef, Development, DHCP, Encoding, Event, Hardware, HTTP, Internet protocol suite, MikroTik, Network-and-equipment, pfSense, Power User, routers, Software Development, SSH, TCP, TLS, UDP | Tagged: 8846 | Leave a Comment »
Posted by jpluimers on 2026/01/01
Cool, since I switched to Let’s Encrypt a long while ago, I missed that various tools now require TLS expiration be no longer than 398 days away (and preferably even 397 days).
So I also missed the reason for that specific number of days. [Wayback/Archive] ssl – Why was 398 days chosen for TLS expiration? – Stack Overflow (thanks [Wayback/Archive] stevendesu and [Wayback/Archive] user10063)
answers it:
366+31+1 = 398 days
It equals one leap year + one month + “a little room to handle the messiness of dates.”
then posts a lot of quotes from references to the history on how that reason came to be. I have archived and listed the links below.
Most of the discussion was during a very hectic time in life: after a single sided bad accident my mentally retarded brother was in and assisting him during his recovery period, I developed cancer and had extensive treatments against it. All the more reason for missing all this:
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Posted in Communications Development, Development, Encryption, https, HTTPS/TLS security, Internet protocol suite, Let's Encrypt (letsencrypt/certbot), Power User, Security, TCP, TLS | Tagged: 138, 195 | Leave a Comment »
