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systemd changes

systemd

systemd-cryptsetup for TrueCrypt

Support for TrueCrypt volumes in Fedora is expanded by systemd-cryptsetup's support for the technology, allowing easy authentication to TrueCrypt volumes during boot.

systemctl

Filtering by unit state

systemctl now supports filtering the unit list output by load state. The --state option will accept any value or a comma-separated list values of LOAD, SUB, or ACTIVE states. For example:

systemctl --state failed

journalctl

Viewing the logs of a specific boot

journalctl -b can be used to look for boot output of a specific boot. For example:

journalctl -b # output from current boot
journalctl -b -1 #output from previous boot

In addition to relative boot sequence, journalctl assigns a 128bit boot ID that can be referenced. For example,

journalctl -b  38fd9c3303574ed38e822233457f6b77 # output from a specific designated boot

Referencing the journal with 'cursors'

journalctl can reference the contents of the journal by a record identifier known as a 'cursor'. Similar to a git hash, the cursor uniquely identifies a point in the journal.

If you add --show-cursor to a journalctl query, the last line of output will contain the cursor value:

journalctl -b -u network --show-cursor --since 15:00
Sep 08 15:37:59 localhost.localdomain network[4074]: [FAILED]
Sep 08 15:37:59 localhost.localdomain systemd[1]: network.service: control process exited, code=exited status=1
Sep 08 15:37:59 localhost.localdomain systemd[1]: Failed to start LSB: Bring up/down networking.
Sep 08 15:37:59 localhost.localdomain systemd[1]: Unit network.service entered failed state.
-- cursor: s=13497722134642a2ac1544bada0c8836;i=1120d;b=8491c05dabd3444ca122e7069b5de0a9;m=db2118a46;t=4e5e7d81c7402;x=d177768ac95df831

The cursor can be used to identify that point in the journal in a broader query to provide context:

journalctl -c "s=13497722134642a2ac1544bada0c8836;i=1120d;b=8491c05dabd3444ca122e7069b5de0a9;m=db2118a46;t=4e5e7d81c7402;x=d177768ac95df831"

Scripts parsing journalctl's output can store the cursor value and use it on their next run to pick up where they left off:

journalctl --after-cursor "s=13497722134642a2ac1544bada0c8836;i=1120d;b=8491c05dabd3444ca122e7069b5de0a9;m=db2118a46;t=4e5e7d81c7402;x=d177768ac95df831"