FAIL: NIECONN_REFUSED (Connection refused), NiRawConnect failed in plugin_fopen()

Problem:

HDB start command will issue the error

"FAIL: NIECONN_REFUSED (Connection refused), NiRawConnect failed in plugin_fopen()"

Scenario:

• Command 'HDB start' failed with below error:FAIL: NIECONN_REFUSED (Connection refused), NiRawConnect failed in plugin_fopen()
• sapcontrol commands also failed with error 'FAIL: NIECONN_REFUSED (Connection refused)'
• service sapstartsrv was not running, checked by command 'ps -ef | grep sapstartsrv'
• From OS log file /var/log/messages, find error occurred during HANA startup

Cause:

Permission error

Troubleshooting:

From the /var/log/messages, the following error was found

"Unable to change to Directory /usr/sap/SID/HDBXX/hostname/trace

Resolution:

The instance profile may be damaged by the unexpected or mistaken shutdown.

The SAPLOCALHOST parameter was pointing to wrong hostname due to which the sapstartsrv agent was not able to find/write the log files under the respective hana trace directory. After the parameter was corrected, the agent was able to start and HANA resumed its services.

Supporting Snote:

2591190 - HANA failed to start with error: FAIL: NIECONN_REFUSED (Connection refused)

Useful Commands:

/usr/sap/SID/SYS/exe/hdb/sapcontrol -prot NI_HTTP -nr <inst num> -function Start

/usr/sap/SID/HDBXX/exe > strace -afH -o /tmp/strace.txt sapcontrol -prot NI_HTTP -nr <inst num> -function Start

Could not Create Full TEXT INDEX- SUM ERROR- MAIN_POSTPROC/JOB_RSFIXUPG

Solution: 

From SE14 ,

Check the indexes that exists for that table.

Usually SAP SUM will try to create a new FULL TEXT INDEX with a different name as a standard and as there are already indexes available, it fails to create the new INDEX with the error "SAP DBTech JDBC: [289]: cannot use duplicate index name:"

From SE11, 

Drop the existing FULL TEXT INDEXES and re-run the SUM STEP

Commands that are helpful : 

DROP FULLTEXT INDEX "<table>~<index>" ON "<Schemaname>"."<table>" 

CREATE FULLTEXT INDEX "<table>~<index>" ON "<Schemaname>"."<table>" ("TXT20") ASYNC LANGUAGE DETECTION ('EN', 'DE') PHRASE INDEX RATIO 0.200000 FUZZY SEARCH INDEX ON SEARCH ONLY ON FAST PREPROCESS OFF TEXT MINING OFF TEXT ANALYSIS OFF TOKEN SEPARATORS '\;,.:-_()[]<>!?*@+{}="&#$/' COMPRESSION LEVEL 0