Troubleshooting for the setup phase

There are several areas during the initialization and setup phase of a new SDS environment that can cause unexpected results. Most of the time the problems come from the following primary areas:

򐂰 Missing or incorrect network definition parameter on one of the sides 򐂰 Missing, incomplete, or incorrectly defined ONCONFIG parameters 򐂰 Missing files that have to be created before startup time

The following sections contain some brief examples that are use cases that should give you an idea of how errors appear, where to find them and the expected change to solve the particular setup problem.

Defining an SDS primary

In this section, we describe defining an SDS primary on a shared memory (shm) communications protocol. One of the prerequisites for the successful

communication between both SDS servers is the definition of at least one on them in DBSERVERNAME or DBSERVERALIASES specified servers with a network based protocol. Trying to set up a primary SDS node based on a local communication with the onmode -d command gives the results shown in Example 6-14 with the messages from the screen and the Log file.

Example 6-14 Defining an SDS primary on shm communication

$>onmode -d set SDS primary sds_prim_shm

Unknown or unsupported type of network protocol for the specified server. onmode: Please check the message log for errors.

$> onstat -m

20:07:03 Logical Log 8 Complete, timestamp: 0x247e5. 20:07:04 'sysha' database built successfully.

20:20:54 Error: Unknown or unsupported type of network protocol,ipcshm, for the specified

server.

The only supported type of network protocol in the SDS environment is TCP. Please modify the network protocol type in the sqlhosts file and rerun the command.

Connection problems between primary and secondary server

In the SDS environment, the currently defined (or set up) pair of primary and secondary servers has to be able to connect each other. Missing or incorrect entries, authentication problems, or network invisibility of the servers are a common source of connection problems.

SQLHOSTS File settings

Assume there is already a running primary server. When trying to startup the secondary you either miss adding the primary server to the sqlhosts on the secondary or one of the connection definition parameters is incorrect, such as the host name or the service number. In that situation, the secondary appears to hang for a longer time. If this happens, check the message file for a message, as shown in Example 6-15. That will give an indication of whether to check the sqlhosts on the SDS secondary side. If this does not help, please check to see if the primary SDS server has changed the communication protocol between the time of the first and secondary setup.

Example 6-15 online.log file with connection problems to the primary SDS server 19:37:56 Event notification facility epoll enabled.

19:37:56 IBM Informix Dynamic Server Version 11.10.UC1 Software Serial Number AAA#B000000

19:37:57 DR: Trying to connect to server, sds_prim_11. If the specified server is not in Online mode, bring it to Online mode. The

secondary server will attempt to connect to the primary for up to 7 minutes.

19:38:02 DR: Trying to connect to server, sds_prim_11. If the specified server is not in Online mode, bring it to Online mode. The

secondary server will attempt to connect to the primary for up to 7 minutes.

19:38:09 DR: Trying to connect to server, sds_prim_11. If the specified server is not in Online mode, bring it to Online mode. The

secondary server will attempt to connect to the primary for up to 7 minutes.

Missing, incomplete, or incorrect ONCONFIG parameters

One of the most common sources of setup problems is forgetting to specify the required ONCONFIG parameters, or setting them with incorrect, or syntactical incorrect, values. In the following sections are several examples of

mis-configured values and the appropriate messages generated by the database server.

SDS_ENABLE on primary or secondary server

If the SDS_ENABLE parameter has been changed manually from the previously set value 1 to 0, or the parameter is removed from the ONCONFIG file, an SDS defined server will not start. The following message will be seen on the screen, as shown in Example 6-16.

Example 6-16 Server start with SDS defined but no SDS_ENABLE set

informix@Linux:/vobs/IDS11/sds11_prim> oninit Can not initialize SDS -

SDS_ENABLE is not set, but the rootchunk indicates a shared disk environment info

If this is the case, set the value back to 1 or add the parameter again.

Invalid page size in SDS_TEMPDBS on the SDS secondary

In order to initialize the secondary SDS server, a temporary dbspace must be specified. One of the parameters to be specified is the page size, which has to be specified in KB. Given an attempt to specify the size in Bytes, or any other invalid value, a message such as the one shown in Example 6-17 will be seen.

Example 6-17 Invalid page size for SDS_TEMPDBS $ oninit

SDS Configuration Error:

SDS_TEMPDBS - Illegal Page Size 19:30:51 SDS Configuration Error: SDS_TEMPDBS - Illegal Page Size The onconfig parameter [SDS_TEMPDBS

tempdbs,/dbspaces/sds11_sec1/sds_sec_tempspace199,2048,0,100000] is invalid.

Invalid SDS_PAGING settings on the SDS secondary

The SDS_PAGING parameter requires two comma separated file names. Example 6-18 on page 131 shows the messages that will be received in attempt to bring up the SDS secondary either with only one specified name or with an incorrect separator.

Example 6-18 Invalid SDS_PAGING settings onlyOnePagefile> oninit

The onconfig parameter [SDS_PAGING /files/sds11_sec1/pagefile] is invalid

WrongSeperator> oninit

The onconfig parameter [SDS_PAGING

/files/sds11_sec1/pagefile;/files/sds11_sec1/pagefile1]

When the SDS_PAGING parameter defined files do not exist, the SDS

secondary server will create the files. In case there is a path specified that points to a non-existing directory, the messages shown in Example 6-19 will be seen.

Example 6-19 Invalid path for SDS_PAGING settings $onstat -m

01:49:56 Can not open /vobs/IDS111/sds11_sec/pagefile

01:49:56 Can not initialize SDS - SDS Initial Connection Failed 01:49:56 IBM Informix Dynamic Server Stopped.

$ oninit

Can not initialize SDS - SDS Initial Connection Failed