SNMP uptime value in hrSystemUptime differs from /proc/uptime in RHEL

Issue

• The value of hrSystemUpdate from our SNMP daemon is different than the value of /proc/uptime (1289636 vs 42962566):

  $ uptime
  23:46:44 up 497 days,  6:02,  1 user,  load average: 0.06, 0.15, 0.15
  
  
  $ cat /proc/uptime
  42962566.94 42701926.83
  
  $ snmpget -mALL -c public -Ovt -v 1 localhost hrSystemUptime.0
  1289636