EXADATA metalink

Oracle Support Document 1070954.1: “Oracle Exadata Database Machine Exachk or HealthCheck"
Oracle Support Document 757552.1: “Oracle Exadata Best Practices "

 Exachk 
Development recommends that the latest exachk be executed with the following frequency:
  • Monthly
  • Week before any planned maintenance activity
  • Day before any planned maintenance activity
  • Immediately after completion of planned maintenance activity or an outage or incident

What are the key Hardware components
  • DB Server
  • Storage Server Cells
  • High Speed Infiniband Switch
  • Cisco Switch
Smart Scan,
  • Smart Flash Cache
  • Storage Index
  • Exadata Hybrid Columnar Compression (EHCC)
  • IORM (I/O Resource Manager)
What is cellcli?
This is the command line utility used to managed the cell storage.


How do you create obtain info on the Celldisks?
What are the Key Software Features?
At the cellcli command line you can issue the “list celldisk” command.

 What are the cellinit.ora and the cellip.ora files used for?

 These files have the hostnames and the ip address of all the nodes in the cluster. They are used to run commands on remote database and cellserver nodes from a local host

 Example:
cat /etc/oracle/cell/network-config/cellinit.ora
ipaddress1=192.168.47.21/24

 $ cat /etc/oracle/cell/network-config/cellip.ora
cell=”192.168.47.21:5042″

 Infiniband
to check if the infiniband as InfiniBand network MTU size Table

 as root
ip addr | grep ib | grep -i mtu | cut -d" " -f 2,5 | sort

e.g. InfiniBand network MTU size Table
ib0: 7000 ib1: 7000 ib2: 7000 ib3: 7000 ib4: 7000 ib5: 7000 ib6: 7000 ib7: 7000


To change as 700 e.g.

1) Edit the appropriate files (for example, /etc/sysconfig/network-scripts/ifcfg-bondib0, /etc/sysconfig/network-scripts/ifcfg-ib0, and /etc/sysconfig/network-scripts/ifcfg-ib1 for the bondib0 interface) and add an entry for MTU=7000. For example:


MTU=7000







2) Reboot the database server and verify the InfiniBand network MTU size is 7000.



NOTE: The InfiniBand fabric must be in "connected" mode before MTU size can be set.



For additional guidance on changing the MTU size in Exadata, please refer to note <Doc 1586212.1>  How to Change MTU Size in Exadata Environment 

Optimize Scan Rates

Confirm correct latency for Small IOs

select WAIT_TIME_MILLI, WAIT_COUNT, WAIT_TIME_MILLI*WAIT_COUNT total_waited_milli ,LAST_UPDATE_TIME, 
LPAD('*', WAIT_TIME_MILLI*WAIT_COUNT/500000, '*') graph 
from v$event_histogram where event='cell single block physical read';

Understand kipmi0 CPU usage





 ExaWatcher
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