Ubuntu16.04から18.04のupgradeに"No new release found."

2 min read


$ sudo do-release-upgrade
Checking for a new Ubuntu release
No new release found.



  • 念のために、release upgraderのPromptがltsであることを確認します。
$ cat /etc/update-manager/release-upgrades
# Default behavior for the release upgrader.

# Default prompting behavior, valid options:
#  never  - Never check for a new release.
#  normal - Check to see if a new release is available.  If more than one new
#           release is found, the release upgrader will attempt to upgrade to
#           the release that immediately succeeds the currently-running
#           release.
#  lts    - Check to see if a new LTS release is available.  The upgrader
#           will attempt to upgrade to the first LTS release available after
#           the currently-running one.  Note that this option should not be
#           used if the currently-running release is not itself an LTS
#           release, since in that case the upgrader won't be able to
#           determine if a newer release is available.


  • do-release-upgradeをデバッグモードで実行します。
$ sudo DEBUG_UPDATE_MANAGER=1 do-release-upgrade
Checking for a new Ubuntu release
MetaRelease.__init__() useDevel=False useProposed=False
/etc/update-manager/meta-release: https://changelogs.ubuntu.com/meta-release
/etc/update-manager/meta-release: https://changelogs.ubuntu.com/meta-release-lts
/etc/update-manager/meta-release: -development
/etc/update-manager/meta-release: -proposed
metarelease-uri: https://changelogs.ubuntu.com/meta-release-lts
result of meta-release download: '<urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:645)>'
NO self.metarelease_information
No new release found.



$ sudo SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt do-release-upgrade