System Basics Introduction
Page 202 7210 SAS D, E, K OS Basic System Configuration Guide
If the profile setting for the clock is ieee1588-2008, the precedence order for the best master
selection algorithm is as follows:
• priority1
• clock class
• clock accuracy
• PTP variance (offsetScaledLogVariance)
• priority2
• clock identity
• steps removed from the grandmaster
The 7210 SAS sets its local parameters as follows:
If the profile setting for the clock is itu-telecom-freq (ITU G.8265.1 profile), the precedence order
for the best master selection algorithm is:
• clock class
• PTSF (Packet Timing Signal Fail) - Announce Loss (Miss 3 announce messages or do not
get Announce message for 6 seconds)priority
Table 25: Local Clock Parameters When Profile is set to ieee1588-2008
Parameter Value
clockIdentity Chassis MAC address following the guidelines of
7.5.2.2.2 of IEEE 1588
clockClass 13 – router configured as ordinary clock master
and is locked to an external reference
14 – router configured as ordinary clock master
and in holdover after having been locked to an
external source
248 – router configured as ordinary clock master
and is in free run or the router is configured as a
boundary clock
255 – router configured as ordinary clock slave
clockAccuracy FE - Unknown
offsetScaledLogVariance FFFF – not computed