Howdy experts,
I am using two Sun-Fire-T200 which is in Cluster mode (sun cluster 3.1). Also Oracle RAC is running on those.
A daylight saving i need to apply in both servers. I am not using any ntp server.
I just plan to change the date with simple date command. Change date in 1st node. Then change in 2nd node.
#date mmddhhmmyy
Now i am confused does this effect to culster system or oracle dbase??
Manually changing the date may have little time difference (3/4second) between 2 nodes.
please advise.
Thanks.
purple
The date command changes the date for Solaris, I think you will find that if you talk to Oracle they will recommend that the Oracle database is shutdown while you change the time especially when it is going back an hour!
Of course the system time can be left alone (at say GMT+0 for example) and a user's TZ environment variable set to BST so that they see the day light saving time changes. What one can do about that for Oracle you will need to find out from an Oracle expert!
if you use the cconsole, date commande will be executed sumultanously on both node.
Now as for the database, I'm not sure that it's a problem for oracle to be up during the change (Not a problem for Sybase) if you can't shut it down (better to do so ..) but for sure you must have no running backup at the time and no transaction or you might have duplicate key problems depending of your database indexes ...
Time between all nodes in a cluster must be synchronized. Whether you synchronize the cluster nodes with any outside time source is not important to cluster operation. The Sun Cluster software employs the Network Time Protocol (NTP) to synchronize the clocks between nodes.
In general, a change in the system clock of a fraction of a second causes no problems. However, if you run date, rdate, or xntpdate (interactively, or within cron scripts) on an active cluster, you can force a time change much larger than a fraction of a second to synchronize the system clock to the time source. This forced change might cause problems with file modification timestamps or confuse the NTP service.
When you install the Solaris Operating System on each cluster node, you have an opportunity to change the default time and date setting for the node. In general, you can accept the factory default.
When you install Sun Cluster software by using the scinstall command, one step in the process is to configure NTP for the cluster. Sun Cluster software supplies a template file, ntp.cluster (see /etc/inet/ntp.cluster on an installed cluster node), that establishes a peer relationship between all cluster nodes. One node is designated the �preferred� node. Nodes are identified by their private host names and time synchronization occurs across the cluster interconnect. For instructions about how to configure the cluster for NTP
Alternately, you can set up one or more NTP servers outside the cluster and change the ntp.conf file to reflect that configuration.
In normal operation, you should never need to adjust the time on the cluster. However, if the time was set incorrectly when you installed the Solaris Operating System and you want to change it