Varnish cache, also known as a reverse caching proxy, is a web application accelerator designed for content-heavy dynamic websites. It is used to cache content in front of the web server and optimize web pages for faster loading times. It handles all inbound requests before they land on your web server’s backend.
In this post, we will show you how to set up the Varnish cache with Nginx on Arch Linux.
Step 1 – Configure Repository
By default, the default repository is outdated in Arch Linux, so you will need to modify the default mirror list if you have not done so already. You can do it by editing the mirrorlist configuration file:
nano /etc/pacman.d/mirrorlist
Remove all lines and add the following lines:
## Score: 0.7, United States Server = http://mirror.us.leaseweb.net/archlinux/$repo/os/$arch ## Score: 0.8, United States Server = http://lug.mtu.edu/archlinux/$repo/os/$arch Server = http://mirror.nl.leaseweb.net/archlinux/$repo/os/$arch ## Score: 0.9, United Kingdom Server = http://mirror.bytemark.co.uk/archlinux/$repo/os/$arch ## Score: 1.5, United Kingdom Server = http://mirrors.manchester.m247.com/arch-linux/$repo/os/$arch Server = http://archlinux.dcc.fc.up.pt/$repo/os/$arch ## Score: 6.6, United States Server = http://mirror.cs.pitt.edu/archlinux/$repo/os/$arch ## Score: 6.7, United States Server = http://mirrors.acm.wpi.edu/archlinux/$repo/os/$arch ## Score: 6.8, United States Server = http://ftp.osuosl.org/pub/archlinux/$repo/os/$arch ## Score: 7.1, India Server = http://mirror.cse.iitk.ac.in/archlinux/$repo/os/$arch ## Score: 10.1, United States Server = http://mirrors.xmission.com/archlinux/$repo/os/$arch
Save and close the file, then update all the package indexes with the following command:
pacman -Syu
Step 2 – Install Varnish Cache
By default, the Varnish package is included in the Arch Linux default repository. You can install it by running the following command.
pacman -S varnish
After the successful installation, start the Varnish service and enable it to start after the system reboot.
systemctl start varnish systemctl enable varnish
By default, Varnish listens on port 6081. You can check it using the following command.
ss -antpl | grep 6081
You will get the following output.
LISTEN 0 0 0.0.0.0:6081 0.0.0.0:* users:(("cache-main",pid=46376,fd=3),("varnishd",pid=46281,fd=3))
LISTEN 0 0 *:6081 *:* users:(("cache-main",pid=46376,fd=5),("varnishd",pid=46281,fd=5))
Step 3 – Install Nginx
Next, you will need to install the Nginx as a backend server. You can install it using the following command.
pacman -S nginx-mainline
Once installed, start and enable the Nginx service using the following command.
systemctl start nginx systemctl enable nginx
By default, Nginx listens on port 80, so you will need to change the Nginx default port to 8080. You can change it by editing the Nginx main configuration file.
nano /etc/nginx/nginx.conf
Change the following line:
listen 8080;
Save and close the file, then restart the Nginx to apply the changes.
systemctl restart nginx
Step 4 – Configure Varnish to Work With Nginx
Next, you will need to edit the Varnish service file and change port 6081 to 80.
nano /usr/lib/systemd/system/varnish.service
Find the following lines:
ExecStart=/usr/sbin/varnishd \
-a :6081 \
-a localhost:8443,PROXY \
-p feature=+http2 \
-f /etc/varnish/default.vcl \
-s malloc,256m
Replace them with the following lines:
ExecStart=/usr/sbin/varnishd \
-a :80 \
-a localhost:8443,PROXY \
-p feature=+http2 \
-f /etc/varnish/default.vcl \
-s malloc,256m
Save and close the file, then reload the systemd daemon to apply the changes.
systemctl daemon-reload
Next, restart the Varnish service using the following command.
systemctl restart varnish
Next, edit the Varnish configuration file and define your backend web server.
nano /etc/varnish/default.vcl
Change the following lines as per your Nginx backend server IP and port.
backend default {
.host = "127.0.0.1";
.port = "8080";
}
Save and close the file when you are done.
Step 5 – Verify Varnish Cache
At this point, the Varnish cache is installed and configured as a front end for the Nginx web server. You can now check it using the curl command.
curl -I http://localhost
If everything is fine, you will get the following output.
HTTP/1.1 200 OK Server: nginx/1.23.3 Date: Thu, 26 Jan 2023 14:41:04 GMT Content-Type: text/html Content-Length: 615 Last-Modified: Tue, 13 Dec 2022 17:30:37 GMT ETag: "6398b6bd-267" X-Varnish: 5 3 Age: 3 Via: 1.1 archlinux (Varnish/7.2) Accept-Ranges: bytes Connection: keep-alive
You can also check the Varnish log to see the caching-related information.
varnishlog
You should see the following output.
- RespHeader Age: 13 - RespHeader Via: 1.1 archlinux (Varnish/7.2) - RespHeader Accept-Ranges: bytes - VCL_call DELIVER - VCL_return deliver - Timestamp Process: 1674744107.428200 0.000149 0.000149 - RespProtocol HTTP/1.1 - RespStatus 304 - RespReason Not Modified - Filters - RespUnset Content-Length: 615 - RespHeader Connection: keep-alive - Timestamp Resp: 1674744107.428263 0.000212 0.000063 - ReqAcct 538 0 538 287 0 287 - End * << Session >> 11 - Begin sess 0 HTTP/1 - SessOpen 49.34.251.188 44732 a0 104.245.35.248 80 1674744107.418188 25 - Link req 12 rxreq - SessClose RX_CLOSE_IDLE 5.016 - End * << Session >> 32771 - Begin sess 0 HTTP/1 - SessOpen 49.34.251.188 44730 a0 104.245.35.248 80 1674744107.512357 31 - SessClose RX_CLOSE_IDLE 5.005 - End * << Session >> 13 - Begin sess 0 HTTP/1 - SessOpen 49.34.251.188 44734 a0 104.245.35.248 80 1674744107.844468 32 - SessClose RX_CLOSE_IDLE 5.001 - End
Conclusion
Congratulations! You have successfully installed and configured the Varnish cache with Nginx on Arch Linux. You can now use Varnish cache as a front-end proxy server to speed up your web server performance. You can test the Varnish cache on dedicated server hosting from Atlantic.Net!
