+++
title = "FAQ"
weight = 1000
+++

### What operating systems are supported?

gVisor requires Linux {{< required_linux >}} ([older Linux][old-linux]).

### What CPU architectures are supported?

gVisor currently supports [x86_64/AMD64](https://en.wikipedia.org/wiki/X86-64)
compatible processors.

### Do I need to modify my Linux application to use gVisor?

No. gVisor is capable of running unmodified Linux binaries.

### What binary formats does gVisor support?

gVisor supports Linux
[ELF](https://en.wikipedia.org/wiki/Executable_and_Linkable_Format) binaries.
Binaries run in gVisor should be built for the
[AMD64](https://en.wikipedia.org/wiki/X86-64) CPU architecture.

### Can I run Docker images using gVisor.

Yes. Please see the [Docker Quick Start](/docs/user_guide/docker/).

## Troubleshooting

### My container runs fine with `runc` but fails with `runsc`

If you’re having problems running a container with `runsc` it’s most likely due
to a compatibility issue or a missing feature in gVisor. See
[Debugging](../debugging/).

### When I run my container, docker fails with: `open /run/containerd/.../<containerid>/log.json: no such file or directory`

You are using an older version of Linux which doesn't support `memfd_create`.
gVisor requires Linux {{< required_linux >}} ([older Linux][old-linux]).

[comment]: # (TODO[gvisor.dev/issue/268] remove when better error messages are implemented.)

### When I run my container, docker fails with: `flag provided but not defined: -console`

You're using an old version of Docker. See [Docker Quick Start](../docker/).

### I can’t see a file copied with: `docker cp`

For performance reasons, gVisor caches directory contents, and therefore it may
not realize a new file was copied to a given directory. To invalidate the cache
and force a refresh, create a file under the directory in question and list the
contents again.

As a workaround, shared root filesystem can be enabled. See [Filesystem](../filesystem/).

This bug is tracked in [bug #4](https://github.com/google/gvisor/issues/4).

Note that `kubectl cp` works because it does the copy by exec'ing inside the
sandbox, and thus gVisor's internal cache is made aware of the new files and
directories.

### I'm getting an error like: `panic: unable to attach: operation not permitted`

Make sure that permissions and the owner is correct on the `runsc` binary.

```bash
sudo chown root:root /usr/local/bin/runsc
sudo chmod 0755 /usr/local/bin/runsc
```

### What's the security model?

See the [Security Model](../../architecture_guide/security/).

[old-linux]: /docs/user_guide/networking/#gso