Troubleshooting Guide#

Frequently Asked Questions (FAQ)#

Question 1: What should I do if I amm running out of space when running Podman?#

Configuring Disk Space#

The containers images are stored in the /var/lib/containers directory when Podman is run by the root user. For standard users, images are typically stored in $HOME/. local/share/containers/storage/.

Since we would be running the experiment in the system as a standard user for security purposes, we would need to increase the storage of the home directory of the standard user for the setup.

We could use the command df -h to view the current storage allocation. When we launch our machines by a cloud provider, the home directory tends to have 1GB of space. It is recommended to increase it by at least 35 GB.

Since RHEL uses Logical Volume Mounts(LVM), you could check the remaining space by the command sudo vgs, to ensure that is has sufficilsent free space to add it to the home directory. Otherwise, there is a separate process (link?) in which we could increase the volume mounts by attaching another data disk.

We could observe that for this volume group rootvg, we have 40 GB of free disk space. This is sufficient as we plan to increase the home directory by only 35 GB.

1.1.1 Increasing the size of home directory by logical mount

To increase the home directory , the command would be:

sudo lvresize -L +<size_to_increase> <filesystem-directory-name>

For our example of increasing by 35 GB, the command would be like:

sudo lvresize -L +35G /dev/mapper/rootvg-homelv

1.1.2 Expanding the directory to the new space

To make use of the newly available space, we need to execute: [is there a command that’s missing?]

Since our home directory is of filesystem type xfs (could be verified by df -h), we will use the below command. Note that for other file systems it may differ.

sudo xfs_growfs /home

To verify that the space has been increased, we will run the df -h command again to verify the new available disk space.

1.1.3: Increase space of /var directory

Podman tends to use the /var as a tmp directory for caching images. Therefore, we will also need to expand the /var directory by using the below commands. It is recommended to have at least 30 GB of /var directory space for this step.

sudo lvresize -L +20G /dev/mapper/rootvg-varlv
sudo xfs_growfs /var

If the logical mount has less free space, kindly attach a new data disk and create a new partition to increase the logical mount space.

For more details, please refer to the documentation for Increasing Logical volume space.

Question 2. How do I make sure that I am running an application in Port 80?#

Opening HTTP Port (80)

If a standard user is launching their application on port 8080, then as an Admininistrator, we will need to follow the below steps to verify the port:

sudo firewall-cmd --add-service=http --permanent

Port forward http port to application port (ex: 8080)

sudo firewall-cmd --add-forward-port=port=80:proto=tcp:toport=8080 --permanent

Refresh Firewall settings

sudo firewall-cmd --reload

List the current firewall settings to verify

sudo `firewall-cmd --list-all