Friday, May 25, 2012

Steps to configure time sync on EMC celerra

EMC Celerra needs to have ntp configured specially if you are using CIFS shares. Active directory server wouldn't issue the kerberos ticket if time is not in sync. We were getting folliwng message with event id 5:

"The kerberos client received a KRB_AP_ERR_TKT_NYV error from the server host/xxx. This indicates that the ticket used against the server is not yet valid(in relationship to the server time)."

We had recently moved our time server to a new IP and these are the steps needed for the time sync:

1. Control station time: This is not critical for AD logins, but nonetheless, it can be set from 2 locations:
  • From GUI: login as root to the control station, go to Manage Control stations , change the IP for the time server and save your settings.
  • or, from command line: edit /etc/ntp.conf and /etc/ntp/step-tickers to have IP addresses of the ntp servers.
2. Time for the data movers: This is critical and this is what is needed for Active directory and CIFS share to work correctly. This can be set from command line(ssh into the control station as nasadmin and then su as root) using following commands:

To see the current settings on the data mover:
server_date server_2 timesvc stats ntp

To change the time servers, following 2 steps are needed:

server_date ALL timesvc stop ntp
server_date ALL timesvc start ntp enter_ip1 enter_ip1

Update: (After I kept getting alerts regarding time sync from celerra, I realized that time sync only works with server_2 or primary data mover and server_3 has to be pointed to internal control station IP, so use the following steps.)

server_date server_2 timesvc start ntp enter_ip1 enter_ip2
server_date server_3 timesvc start ntp
 (use the spaces between ip addresses if you have multiple hosts)
(and is the standard internal IP for control station. Since server_3 can only reach that network, it would be good with that)

Give it a minute or so and you can check the new time using:
server_date ALL

And don't worry about the lag between active and passive  data movers, that is normal.
If the control station is also time synced, time between server_2 and server_3 should be same as well.

1 comment:

Anonymous said...

I am not really a EMC guy, so this posting saved me some serious time. Thanks