Tuesday, October 19, 2010

RAC Management tools
  • olsnodes
    • olsnodes command provides the list , their VIP and numbers of nodes in the cluster. It is found at $ORA_CRS_HOME/bin directory
  • Oifcfg
    • Oracle Interface configuration tool (oifcfg) helps to define and administer network interfaces
      1. oifcig iflist
      2. oifcfg setif
      3. oifcfg getif
      4. oifcfg delif
  • crsctl
    • crsctl commands perform the following tasks on Oracle clusterware:
      • Starting and stopping Oracle clusterware resources
        •  crsctl start cluster
        • crsctl stop cluster
        • crsctl check cluster
      • Enabling and disabling Oracle clusterware daemons
      • Checking the health of the cluster
        • crsctl check cluster
        • crsctl check crs
        • crsctl check resource
        • crsctl check ctss
      •  Managing thrid party application resources
      • Integrating Intelligent Platform mangement interface (IPMI) with Oracle clusterware
      • Debugging Oracle clusterware components

Monday, October 11, 2010

RAC Preinstallation Check

  • Memory requirement
    • Every node should have minimum of 1 GB
    • prtconf | grep Memory
  • Swap requirement
    • Swap space should be set to twice the amount of RAM for systems with 2GB of RAM or less. For systems with 2GB to 8GB, use swap space equal to RAM. For systems over 8GB , use .75 times of the size of RAM
    • Verify the swap is set to .75 times the size of RAM
    • swap -s
  • tmp space
    • Atleast 400MB of disk space is required in /tmp
    • df -h /tmp
  • Maximum Open File descriptors
    • To check ulimit -n
    • To set ulimit -n <new value>
  • Network requirements
  • You should have minimum of 2 network interfaces per node
    • dladm show-link
  • You should have three network address for each node
    • Public IP address
      • ping <public-node-name>
    • Virtual IP address : Used by applications for failover in case of node failure
      • Do not plump Virtual ip address. Pinging virutal address should result in failure
      • The virtual IP address is on the same subnet as your public interface
    • Private IP address: Used by Oracle clusterware for internode communication
      • It should be on the same subnet reserved for private networks such as 10.0.0.0 or 192.168.0.0
      • It should use dedicated switches or physically separate private network, reachable only by the cluster member nodes, prefably using high-speed NICs
      • It cannot be registered on the same subnet that is registered to a public IP address
      • ping <private-node-name>
  • The /etc/hosts should have following entries for each node
    • Your public node name,public node name.domainname
    • Your private node name, private nodename.domainname
    • Your vip node name, vip nodename.domainname
  • About interfaces on all nodes
    • The public interface names associated with the network adapters for each network must be the same on all nodes and the private interface names assoicated with the network adaptors should be the same For example: With a two-node cluster, you cannot configure network adapters on node1 with eth0 as the public interface, but on node2 have eth1 as the public interface. Public interface names must be the same, so you must configure eth0 as public on both nodes. You should configure the private interfaces on the same network adapters as well. If eth1 is the private interface for node1, then eth1 should be the private interface for node2.
  • SSH connectivity
    • Passwordless SSH connectivity should be establed between all cluster nodes.  OUI can automatically configure password SSH connectivity. For that to happen, make sure there are no stty commands in oracle user probile. By default OUI searches for public keys in /usr/local/etc directory and it searches for ssh-keygen binaries in /usr/local/bin directory. However, in Solaris public keys are found under /etc/ssh and ssh-keygen binaries are under /usr/bin. So the following softlinks needs to be created prior to starting OUI
      • ln -s /etc/ssh /usr/local/etc
      • ln -s /usr/bin /usr/local/bin
    • Create the links as mentioned above and invoke sshsetup.sh script in staging area. Verify you can ssh without password
      • ssh <node1> date
      • ssh <node2> date
  • More info
  • Additional notes
  • Verifying the existance of public IPs and VIPs
    • Use ypwhich, ypcat hosts    
  • Network setup : Refer to IP services guide for details
    • Issue dladm show-link command to find out installed interfaces   
      • Issue ifconfig -a command to determine which interface is plumped 
        • To configure and plump an interface named el000g1
          • ifconfig e1000g1 plump up      
          •  ifconfig e1000g1 <address> netmask+  
          • Verify that interface is up : ifconfig -a    
        • To make interface e1000g1 plumping persistent across reboots
          • Create a file /etc/hostname.e1000g1      
          • Add the address of the interface to this file
          • vi /etc/hostname.e1000g1    
          • Add entries for the new interface into /etc/inet/ipnodes     
        • Perform a reconfiguration reboot
          • reboot -- -r       
        • Verfiy that interface is up : ifconfig -a      
      • Solaris supports two types of interfaces
        • Legacy interfaces
          • They are DLPI and GLDv2 interfaces. Some legacy types are eri, qge,and ce  
        • Non-VLAN interfaces
          • These interfaces are GLDv3 interfaces.    
          •  bge,xge and e1000g are non-VLAN interfaces