Allow to attach process with gdb

Since DDT is not anymore available, it would be useful to be able to use gdb to attach to a process with gdb --pid 1234. But I have the following error when trying to do it:

Could not attach to process.  If your uid matches the uid of the target
process, check the setting of /proc/sys/kernel/yama/ptrace_scope, or try
again as the root user.  For more details, see /etc/sysctl.d/10-ptrace.conf

Apparently, it can be changed: https://askubuntu.com/questions/41629/after-upgrade-gdb-wont-attach-to-process

Is it possible?