If for some reason adding a PHP-FPM pool doesn’t work, and you don’t know why, and you’ve spent 20 minutes bashing your head on it even though you’ve added the config file and everything.. make sure you’ve remembered to change the poolname at the top of the file from the [www] you copied from the www.conf file
I know most folk these days are using ansible and stuff to do this, but we add sites so rarely it’s just not worth setting up
I’ve been reading lots over the last little while, on how to stay cool in the current heatwave. This is all the recommendations I have. I’ll follow this up with explanations of each suggestion in another post later — writing this has taken a lot out of me! Links are for example, buy what’s available and fits your needs 🙂
The UK is not set up for heat waves of up to 40c, thousands of people will die, we may have power and water outages.
Do not do any of these things. They will harm you!
Terrible one-liner to make this easier to remember;
for i in $(varnishadm vcl.list | grep cold | awk '{print $4}') ; do varnishadm "vcl.discard $i" ; doneIn a fit of desperation, I tweeted asking for *simple*, *easy*, cheap recipes. This is what I got in return. I’m totally posting this so it’s really easy to print them.
Shamelessly stolen from wikipedia because they’re thinking about removing this, as “Wikipedia is not a howto”. *sigh*.
With kernel version 3.5 and over, as well as kernel version 2.6.32-303 and over, it is likely better to use 1 for cases where 0 used to be optimal.
To temporarily set the swappiness in Linux, write the desired value (e.g. 10) to /proc/sys/vm/swappiness using the following command, running as root user:
# Set the swappiness value as root echo 10 > /proc/sys/vm/swappiness # Alternatively, run this sysctl -w vm.swappiness=10 # Verify the change cat /proc/sys/vm/swappiness 10 # Alternatively, verify the change sysctl vm.swappiness vm.swappiness = 10
Permanent changes are made in /etc/sysctl.conf via the following configuration line (inserted, if not present):
vm.swappiness = 10
10 is generally good for ‘I don’t want swapping to happen except if you *really* need it.
Are you getting a weird error from varnish that you’re having trouble working out? Is it cryptically saying that there’s an issue with your host definition in your VCL?
Expected ID got ';'
(program line 165), at
('input' Line 20 Pos 30)
.first_byte_timeout = 120;
-----------------------------#
You need to add a time unit to your timeout definitions — ‘s’ for seconds, ‘m’ for minutes. Stupid cryptic error is dumbly cryptic. Grrr.
https://varnish-cache.org/lists/pipermail/varnish-bugs/2011-August/003983.html
So, you have a Varnish server running systemd, which is behind a reverse proxy for SSL like nginx, and you can’t work out how to make varnishncsa log IP addresses from a specified header? Well, it’s a bit of a pain in the neck really. You need to override the systemd service file, which is like systemd’s version of the init scripts. Due to it being systemd, this is not just a case of editing a file…
For Debian, you can use the service file below, and paste it into
/etc/systemd/system/varnishncsa.service
Once done, you need to reload systemd’s service listing itself;
$ systemctl daemon-reload
Congratulations, you now have varnishncsa logs including the visitor’s real IP address, as specified by Nginx. Change the name in “{X-Forwarded-For}” to change the header name, for example if you want CloudFlare’s view of the client’s IP address, use “CF-Connecting-IP”
[Service]
RuntimeDirectory=varnishncsa
Type=forking
PIDFile=/run/varnishncsa/varnishncsa.pid
User=varnishlog
Group=varnish
ExecStart=/usr/bin/varnishncsa -a -w /var/log/varnish/varnishncsa.log -D -P /run/varnishncsa/varnishncsa.pid -F '%%{X-Forwarded-For}i %%l %%u %%t "%%r" %%s %%b "%%{Referer}i" "%%{User-agent}i"'
ExecReload=/bin/kill -HUP $MAINPID
If SystemD MariaDB/MySQL is failing to start, make sure your logs directory is set correctly. Sometimes this is caused by failing to correctly make sure the directory is moved.
You’ll see an error log in the journal as follows;
Nov 27 18:24:55 db-a mysqld[28677]: 2017-11-27 18:24:55 140273229838208 [Note] /usr/sbin/mysqld (mysqld 10.2.10-MariaDB-10.2.10+maria~jessie-log) starting as process 28677
Nov 27 18:24:55 db-a systemd[1]: mariadb.service: main process exited, code=exited, status=1/FAILURE
Nov 27 18:24:55 db-a systemd[1]: Failed to start MariaDB database server.
Nov 27 18:24:55 db-a systemd[1]: Unit mariadb.service entered failed state.
This is complicated, but I need to remember this, so I want to put it somewhere. You need to add this to apache config / .htaccess file to get apache to correctly set the HTTPS environment variable when the backend is secure. It trips based on the X-Forwarded-Proto header being ‘https’.
SetEnvIf X-Forwarded-Proto "https" HTTPS=on
For some reason, grep, thought that a “HTML document, Non-ISO extended-ASCII text, with very long lines” was a binary, so refused to print contents.
TIL about -a. In grep, -a tells grep to process a binary file as if it were text. This means, if grep incorrectly thinks a file is binary, it’ll still work with it.
That cost me at least 2 hours of scratching my head, wondering why my regex wasn’t working as it should…