Known issues

Linux Windows

This page describes known issues that you might run into while using Compute Engine.

General issues

The CPU utilization observability metric is incorrect for VMs that use one thread per core

If your VM's CPU uses one thread per core, the CPU utilization Cloud Monitoring observability metric in the Compute Engine > VM instances > Observability tab only scales to 50%. Two threads per core is the default for all machine types, except Tau T2D. For more information, see Set number of threads per core.

To view your VM's CPU utilization normalized to 100%, view CPU utilization in Metrics Explorer instead. For more information, see Create charts with Metrics Explorer.

Google Cloud console SSH-in-browser connections might fail if you use custom firewall rules

If you use custom firewall rules to control SSH access to your VM instances, you might not be able to use the SSH-in-browser feature.

To work around this issue, do one of the following:

Enable Identity-Aware Proxy for TCP to continue connecting to VMs using the SSH-in-browser Google Cloud console feature.
Recreate the default-allow-ssh firewall rule to continue connecting to VMs using SSH-in-browser.
Connect to VMs using the Google Cloud CLI instead of SSH-in-browser.

Deleting specific reservations stops VMs from consuming other reservations

If you delete a specific reservation that was consumed by one or more VMs, those VMs cannot consume any other reservation.

Optionally, to prevent this issue, delete the VMs that are consuming a specific reservation before deleting the specific reservation.
To fix this issue:
1. Recreate a new specific reservation with the same name and properties as the deleted specific reservation.
2. Stop and start the affected VMs.

Learn more about deleting reservations.

Moving VMs or disks using the `moveInstance` API or the gcloud CLI causes unexpected behavior

Moving virtual machine (VM) instances using the gcloud compute instances move command or the project.moveInstance method might cause data loss, VM deletion, or other unexpected behavior. When you move VMs, we recommend that you follow the instructions in Move a VM instance between zones or regions.

Disks attached to VMs with `n2d-standard-64` machine types do not consistently reach performance limits

Persistent disks attached to VMs with n2d-standard-64 machine types do not consistently reach the maximum performance limit of 100,000 IOPS. This is the case for both read and write IOPS.

Temporary names for disks

During virtual machine (VM) instance updates initiated using the gcloud compute instances update command or the instances.update API method, Compute Engine might temporarily change the name of your VM's disks, by adding of the following suffixes to the original name:

-temp
-old
-new

Compute Engine removes the suffix and restores the original disk names as the update completes.

Increased latency for some persistent disks caused by disk resizing

In some cases, resizing large persistent disks (~3 TB or larger) might be disruptive to the I/O performance of the disk. If you are impacted by this issue, your persistent disks might experience increased latency during the resize operation. This issue can impact persistent disks of any type.

Known issues for Linux VM instances

repomd.xml signature could not be verified

On Red Hat Enterprise Linux (RHEL) or CentOS 7 based systems, you might see the following error when trying to install or update software using yum. This error shows that you have an expired or incorrect repository GPG key.

Sample log:

[root@centos7 ~]# yum update


...

google-cloud-sdk/signature                                                                  | 1.4 kB  00:00:01 !!!
https://packages.cloud.google.com/yum/repos/cloud-sdk-el7-x86_64/repodata/repomd.xml: [Errno -1] repomd.xml signature could not be verified for google-cloud-sdk
Trying other mirror.

...

failure: repodata/repomd.xml from google-cloud-sdk: [Errno 256] No more mirrors to try.
https://packages.cloud.google.com/yum/repos/cloud-sdk-el7-x86_64/repodata/repomd.xml: [Errno -1] repomd.xml signature could not be verified for google-cloud-sdk

Resolution:

To fix this, disable repository GPG key checking in the yum repo configuration by setting repo_gpgcheck=0. In supported Compute Engine base images this setting might be found in /etc/yum.repos.d/google-cloud.repo file. However, your VM can have this set in different repository configuration files or automation tools.

Yum repositories do not usually use GPG keys for repository validation. Instead, the https endpoint is trusted.

To locate and update this setting, complete the following steps:

Look for the setting in your /etc/yum.repos.d/google-cloud.repo file.

cat /etc/yum.repos.d/google-cloud.repo


[google-compute-engine]
name=Google Compute Engine
baseurl=https://packages.cloud.google.com/yum/repos/google-compute-engine-el7-x86_64-stable
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg
   https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
[google-cloud-sdk]
name=Google Cloud SDK
baseurl=https://packages.cloud.google.com/yum/repos/cloud-sdk-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg
   https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg

Change all lines that say repo_gpgcheck=1 to repo_gpgcheck=0.

sudo sed -i 's/repo_gpgcheck=1/repo_gpgcheck=0/g' /etc/yum.repos.d/google-cloud.repo

Check that the setting is updated.

cat /etc/yum.repos.d/google-cloud.repo

[google-compute-engine]
name=Google Compute Engine
baseurl=https://packages.cloud.google.com/yum/repos/google-compute-engine-el7-x86_64-stable
enabled=1
gpgcheck=1
repo_gpgcheck=0
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg
   https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
[google-cloud-sdk]
name=Google Cloud SDK
baseurl=https://packages.cloud.google.com/yum/repos/cloud-sdk-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=0
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg
   https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg

GPG error: EXPKEYSIG 3746C208A7317B0F when updating packages

On Debian systems and Ubuntu systems where you manually installed the Google Cloud CLI, including your local workstation, you might encounter an error similar to the following example:

W: An error occurred during the signature verification.
The repository is not updated and the previous index files will be used.
GPG error: http://packages.cloud.google.com/apt cloud-sdk-stretch InRelease:
The following signatures were invalid: EXPKEYSIG 3746C208A7317B0F
Google Cloud Packages Automatic Signing Key <gc-team@google.com>

This error prevents you from obtaining the latest updates for several Google Cloud tools, including the following items:

Compute Engine guest environment
Google Cloud CLI with the Google Cloud CLI
Cloud Logging agent

To resolve this error, get the latest valid apt-key.gpg key file from https://packages.cloud.google.com:

Debian systems

Run the following command:

curl https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -

Ubuntu systems