If you're experiencing PHP build failing you need to check the following requirements in order to fix the issue
1st case :
you've low on RAM we recommend adding at least 1.5-2 Gb of available ram to compile PHP 7.xx and 8.xx as the compiler needs more memory for this version of PHP
you can check if you've sufficient RAM by this command :
free -h
example output :
root@server:~# free -h
total used free shared buff/cache available
Mem: 1.9Gi 328Mi 90Mi 56Mi 1.4Gi 1.5Gi
Swap: 2.0Gi 38Mi 1.9Gi
here you can see Mem which indicates the total RAM and you need to check the `available` memory which should be more than 1.5Gb listed
Also for low memory servers, we always recommend adding at least 2Gb of Swap memory to prevent OOM (Out of memory) incidents.
2nd Case :
You're using an outdated OS that is already ON EOL period
Like Centos 6 and Centos 8 which are already in the EOL period and many repositories are disabled in this OS and you may experience non-availability of packages and dependencies which are required to build the PHP.
We always recommend upgrading you to Following OS :
Centos 7
Centos 8 stream
AlmaLinux 8
Rocky Linux 8
Oracle Linux 7 and 8
3rd Case :
Internet issue/Resolver issue
We've seen some cases where the OS resolver is not correctly set and many packages are not downloading due to the resolver failing.
Ensure you have the correct resolver added in /etc/resolv.conf
you can add this lines at the end of the file in /etc/resolv.conf :
nameserver 1.1.1.1 nameserver 8.8.8.8
* Your server provider might also have some custom resolvers
Now lock the file :
chattr +i /etc/resolv.conf
The next step is to reboot the server :
reboot
Make sure you check the logs as it can be also any other reason