a technical IT blog
Archive for the ‘All articles’ Category.
If you’re using Postfix and Amavis, you may be seeing “Error: queue file write error”, especially with larger than usually email rates.
Here is what you can do to get rid of them.
Continue reading ‘“Error: queue file write error” with Postfix and Amavis’ »
If you have a large MySQL dump file, but only need to restore a single table, you may use the following:
Continue reading ‘restoring a single table from a large MySQL dump file’ »
If your server happened to crash, Postgres database is corrupted, but didn’t contain too precious information, you may try the following fix.
The typical symptoms of a corrupted Postgres database would be like below:
Continue reading ‘repairing broken PostgreSQL databases / tables’ »
If you ever wondered how to generate a sitemap file for Mailman (the GNU Mailing List Manager), to be submitted i.e. to Google, here is how.
All you have to do is replacing a few variables, and submitting the sitemap to your favourite search engine.
It is based on a real website running Mailman: http://lists.wpkg.org
With below code, it takes around 5 seconds to generate a sitemap consisting of 10000 articles.
If you’re looking for a way to add Facebook, Twitter, Google+ buttons in your MediaWiki installation, you may be disappointed – there are no plugins offering all three social buttons. There are some other plugins, but they are often outdated, don’t work with current MediaWiki versions, or are simply broken.
How about doing a small change to your skin then and adding the buttons yourself?
Continue reading ‘Facebook, Twitter, Google+ buttons in MediaWiki’ »
Some datacenters and hosting providers in New York area are still down following the Sandy storm hurricane.
One of them is ezzi.net, which is offline since around 1 am, 30-Oct-2012, CET time (or, 8 pm, 29-Oct-2012 EDT).
Continue reading ‘ezzi.net still down following Sandy storm hurricane’ »
Ever wondered what is hammering your disk so now and then, but couldn’t figure out with top / htop and similar? Annoying, but constant 100-200 kB/s writes? Or, simply blktrace was an overkill (or not supported by the kernel)?
Continue reading ‘simple filesystem read/write tracing with /proc/sys/vm/block_dump’ »
You’ve probably used port forwarding available in OpenSSH to securely forward selected ports to selected hosts.
What if you wanted to securely push i.e. all web traffic from your PC/laptop through some other server running?
OpenSSH and its SOCKS capability to the rescue!
Continue reading ‘SOCKS proxy with OpenSSH (instead of port forwarding)’ »
It’s 22 Oct 2012, 18:30 UTC and it’s not possible to use Amazon EC2 web interface located at https://console.aws.amazon.com/ec2/:
# curl https://console.aws.amazon.com/ec2/
Http/1.1 Service Unavailable
Continue reading ‘Amazon EC2 outage + web interface not working’ »
Increasing number of instances running on EC2, ever wondered how to get their list of IP addresses, including elastic IPs, from CLI (i.e. to make sure you don’t have any servers with proxy or SMTP open relay)?
Here is a small bash script that will do it.
Continue reading ‘listing your EC2 instances IP addresses from command line’ »