Here’s the command to extend your regional persistent disks.

<pre lang="bash">
gcloud compute disks resize disk-name \
--size 100 \
--project project-id \
--region us-central1

Or you can specify by zone.

<pre lang="bash">
gcloud compute disks resize disk-name \
--size 100 \
--project project-id \
--zone us-central1-c

Display the updated disk details.

<pre lang="bash">
gcloud compute disks list \
--filter="name=disk-name" \
--project project-id

Although you’ve increased disk size, the file system doesn’t know the extra space. Run this (for XFS).

<pre lang="bash">
xfs_growfs /dev/sdb