root@Aspire-5738ZG:~# apt update
Hit:1 http://fr.archive.ubuntu.com/ubuntu xenial InRelease
Hit:2 http://security.ubuntu.com/ubuntu xenial-security InRelease
0% [1 InRelease gpgv 247 kB] [Waiting for headers]Couldn't create tempfiles for splitting up /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial_InReleErr:1 http://fr.archive.ubuntu.com/ubuntu xenial InRelease
Could not execute 'apt-key' to verify signature (is gnupg installed?)
0% [2 InRelease gpgv 102 kB] [Waiting for headers]Couldn't create tempfiles for splitting up /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_xenial-securityErr:2 http://security.ubuntu.com/ubuntu xenial-security InRelease
Could not execute 'apt-key' to verify signature (is gnupg installed?)
Hit:3 http://fr.archive.ubuntu.com/ubuntu xenial-updates InRelease
0% [3 InRelease gpgv 102 kB] [Waiting for headers]Couldn't create tempfiles for splitting up /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-updateErr:3 http://fr.archive.ubuntu.com/ubuntu xenial-updates InRelease
Could not execute 'apt-key' to verify signature (is gnupg installed?)
Hit:4 http://fr.archive.ubuntu.com/ubuntu xenial-backports InRelease
0% [4 InRelease gpgv 102 kB]Couldn't create tempfiles for splitting up /var/lib/Err:4 http://fr.archive.ubuntu.com/ubuntu xenial-backports InReleasease
Could not execute 'apt-key' to verify signature (is gnupg installed?)
Reading package lists... Done
Building dependency tree
Reading state information... Done
227 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: chown to _apt:root of directory /var/lib/apt/lists/partial failed - SetupAPTPartialDirectory (30: Read-only file system)
W: chmod 0700 of directory /var/lib/apt/lists/partial failed - SetupAPTPartialDirectory (30: Read-only file system)
W: Not using locking for read only lock file /var/lib/apt/lists/lock
W: Problem unlinking the file /var/lib/apt/lists/partial/.apt-acquire-privs-test.QzmPqM - IsAccessibleBySandboxUser (30: Read-only file system)
W: Problem unlinking the file /var/lib/apt/lists/partial/.apt-acquire-privs-test.q52x5i - IsAccessibleBySandboxUser (30: Read-only file system)
W: Problem unlinking the file /var/lib/apt/lists/partial/.apt-acquire-privs-test.o2SgKP - IsAccessibleBySandboxUser (30: Read-only file system)
W: Problem unlinking the file /var/lib/apt/lists/partial/.apt-acquire-privs-test.a31Zom - IsAccessibleBySandboxUser (30: Read-only file system)
W: Problem unlinking the file /var/lib/apt/lists/partial/fr.archive.ubuntu.com_ubuntu_dists_xenial_InRelease - PrepareFiles (30: Read-only file system)
W: chown to _apt:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chmod 0600 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial_InRelease failed - Item::QueueURI (30: Read-only file system)
W: Problem unlinking the file /var/lib/apt/lists/partial/security.ubuntu.com_ubuntu_dists_xenial-security_InRelease - PrepareFiles (30: Read-only file system)
W: chown to root:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial_InRelease failed - 400::URIFailure (30: Read-only file system)
W: chmod 0644 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial_InRelease failed - 400::URIFailure (30: Read-only file system)
W: chown to _apt:root of file /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_xenial-security_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chmod 0600 of file /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_xenial-security_InRelease failed - Item::QueueURI (30: Read-only file system)
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://fr.archive.ubuntu.com/ubuntu xenial InRelease: Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: chown to root:root of file /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_xenial-security_InRelease failed - 400::URIFailure (30: Read-only file system)
W: chmod 0644 of file /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_xenial-security_InRelease failed - 400::URIFailure (30: Read-only file system)
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://security.ubuntu.com/ubuntu xenial-security InRelease: Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Problem unlinking the file /var/lib/apt/lists/partial/fr.archive.ubuntu.com_ubuntu_dists_xenial-updates_InRelease - PrepareFiles (30: Read-only file system)
W: chown to _apt:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-updates_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chmod 0600 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-updates_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chown to root:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-updates_InRelease failed - 400::URIFailure (30: Read-only file system)
W: chmod 0644 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-updates_InRelease failed - 400::URIFailure (30: Read-only file system)
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://fr.archive.ubuntu.com/ubuntu xenial-updates InRelease: Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Problem unlinking the file /var/lib/apt/lists/partial/fr.archive.ubuntu.com_ubuntu_dists_xenial-backports_InRelease - PrepareFiles (30: Read-only file system)
W: chown to _apt:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-backports_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chmod 0600 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-backports_InRelease failed - Item::QueueURI (30: Read-only file system)
W: chown to root:root of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-backports_InRelease failed - 400::URIFailure (30: Read-only file system)
W: chmod 0644 of file /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_xenial-backports_InRelease failed - 400::URIFailure (30: Read-only file system)
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://fr.archive.ubuntu.com/ubuntu xenial-backports InRelease: Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/xenial/InRelease Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/xenial-updates/InRelease Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/xenial-backports/InRelease Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/xenial-security/InRelease Could not execute 'apt-key' to verify signature (is gnupg installed?)
W: Some index files failed to download. They have been ignored, or old ones used instead.
W: Problem unlinking the file /var/cache/apt/pkgcache.bin - RemoveCaches (30: Read-only file system)
W: Problem unlinking the file /var/cache/apt/srcpkgcache.bin - RemoveCaches (30: Read-only file system)
root@Aspire-5738ZG:~#