Introduction

phosphor-time-manager is the time manager service that implements dbus interface xyz/openbmc_project/Time/EpochTime.interface.yaml. User can get or set the BMC's or HOST's time via this interface.

General usage

The service xyz.openbmc_project.Time.Manager provides two objects on dbus:

• /xyz/openbmc_project/time/bmc
• /xyz/openbmc_project/time/host

where each object implements interface xyz.openbmc_project.Time.EpochTime.

User can directly get or set the property Elasped of the objects to get or set the time. For example on an authenticated session:

• To get BMC's time:

  ### With busctl on BMC
  busctl get-property xyz.openbmc_project.Time.Manager \
      /xyz/openbmc_project/time/bmc xyz.openbmc_project.Time.EpochTime Elapsed
  
  ### With REST API on remote host
  curl -b cjar -k https://bmc-ip/xyz/openbmc_project/time/bmc
  

• To set HOST's time:

  ### With busctl on BMC
  busctl set-property xyz.openbmc_project.Time.Manager \
      /xyz/openbmc_project/time/host xyz.openbmc_project.Time.EpochTime \
      Elapsed t <value-in-microseconds>
  
  ### With REST API on remote host
  curl -b cjar -k -H "Content-Type: application/json" -X PUT \
      -d '{"data": 1487304700000000}' \
      https://bmc-ip/xyz/openbmc_project/time/host/attr/Elapsed
  

Time settings

Getting BMC or HOST time is always allowed, but setting the time may not be allowed depending on below two settings in settings manager.

• TimeSyncMethod
  • NTP: Time is set via NTP server.
  • MANUAL: Time is set manually.
• TimeOwner
  • BMC: BMC owns the time and can set the time.
  • HOST: Host owns the time and can set the time.
  • SPLIT: BMC and Host owns separate time.
  • BOTH: Both BMC and Host can set the time.

A summary of which cases the time can be set on BMC or HOST:

Special note on host on

When host is on, the changes of the above time mode/owner are not applied but deferred. The changes of the mode/owner are saved to persistent storage.

When host is off, the saved mode/owner are read from persistent storage and are applied.

Note: user can set the time mode and owner in settings daemon at any time, but time manager applying them is governed by the above condition.