apptainer-sign - Man Page

• Sign a container image using the default PGP key: apptainer sign path/to/image.sif
• Sign a container image using a specific private key file: apptainer sign --key path/to/private.pem path/to/image.sif
• Sign a container image using a specific PGP key index: apptainer sign [-k|--keyidx] key_index path/to/image.sif
• Sign a specific object group within the image: apptainer sign [-g|--group-id] group_id path/to/image.sif
• Sign a specific object by ID within the image: apptainer sign [-i|--sif-id] object_id path/to/image.sif
• Display help: apptainer sign [-h|--help]

tldr.sh

apptainer sign [sign options...]

The sign command allows a user to add one or more digital signatures to a SIF
 image. By default, one digital signature is added for each object group in
 the file.

Key material can be provided via PEM-encoded file, or an entity in the PGP
 keyring. To manage the PGP keyring, see 'apptainer help key'.

-g, --group-id=0 sign objects with the specified group ID

-h, --help[=false] help for sign

--key="" path to the private key file

-k, --keyidx=0 PGP private key to use (index from 'key list --secret')

-i, --sif-id=0 sign object with the specified ID

  Sign with a private key:
  $ apptainer sign --key private.pem container.sif

  Sign with PGP:
  $ apptainer sign container.sif

apptainer(1)

2-Feb-2026 Auto generated by spf13/cobra

apptainer(1).