DB2 database migration FAQs (1)

Installation and configuration

After you reinstall DB2 in Linux, you cannot create an instance of DB2INST1, prompting that the instance already exists.

Solution:Delete the/var/db2/v81 directory and recreate the instance;

Cause analysis:Before you reinstall DB2, You Need To uninstall the original DB2 installation environment. An important step is to use the db2idrop command to delete the DB2INST1 instance. If you do not delete the instance, after you install DB2 again, you cannot create a database instance with the same name. The db2idrop command is in the/opt/IBM/db2/V8.1/instance directory. The following is an example:

Listing 1. db2idrop command example

/Opt/IBM/db2/V8.1/instance/db2idrop db2inst1

You cannot create an instance after installing DB2 in Solaris 5.8, prompting you to adjust shmmax.

Solution:Edit the/etc/system file, modify the shared memory parameters and message queue values, restart the machine, and then create an instance;

Cause analysis:DB2 requires IPC communication on UNIX systems. Therefore, Kernel Parameter shared memory and message queue are key indicators. If the number cannot meet the DB2 requirements, DB2 cannot work normally, its specific numbers are hard to remember, but you can view db2diag. log, which records the specific numbers required by DB2. Follow this number to update the kernel parameters.

Can the DB2 Runtime Client not install the development kit, but only install components that are sufficient for the Client to simulate the actual application environment of the customer for testing?

Solution:The DB2 Runtime Client does not contain the development kit. Its function is to provide only the component packages that the client works on.

One bare device cannot be allocated to two databases at the same time, so that two database servers cannot be created to share the same bare device.

Solution:Create two databases on different instances, stop one instance, start the second instance, and allocate bare devices to the database on the active instance, after the allocation is completed, stop the active instance, start the first instance, and repeat the previous allocation of bare devices to the first instance to stop a database, the bare device data can be completely taken over by another database for sharing.

Cause analysis:A container cannot be assigned to two active databases at the same time. You must operate on two instances. When assigned to one instance, the other instance must be inactive.

After installing DB2 on Linux, you cannot bind the License and report the DBI1430N error.

Solution:

1. Update the system time to the current time. Use the DATE command in Linux;

2. Bind The License using the db2licm command:

Listing 2. Example of binding a License command

./Db2licm-a db2ese. lic

Failed to create DB2 instance on Linux, error code DBI1281E is returned

Solution:Set the host name correctly;

Cause analysis:When creating an instance in DB2, you must take the host name. If the host name is set incorrectly, an error indicating that the instance cannot be initialized is reported, that is, DBI1281E. You can use uname or hostname to check whether a host name exists, you can use the ping command to verify whether the host name is correct. If the ping rule is incorrect, you can also check/etc/hosts to check whether the ing between the IP address and the host name is correct.