"Problem occurred while connecting to the Update Manager server" while accessing Update Manager from the webclient

Products

VMware vCenter Server

Issue/Introduction

The purpose of this KB is to how to recover the vmware-updatemgr service on VCSA 6.5 by manually replacing the odbc.ini file.
The procedure was tested only on VCSA 6.5 U2 with embedded PSC.

Symptoms:

Unable to access update-manager form webclient.
Error : "Problem occurred while connecting to the Update Manager server. See the vsphere Web Client Logs for more details".
vmware-updatemgr service failing to start.
In the updatemgr-utility.log file, you see entries similar to:

[2019-06-19 11:23:45:612 '' 140088508442560 DEBUG] [installerRunDBCommand, 265] [DATABASE] op name = dbcreate
[2019-06-19 11:23:45:612 '' 140088508442560 ERROR] [installerRunDBCommand, 242] [DATABASE] InstallerRunDBCommand::InitDsnInfo() relies on crypto, using plaintext vum4linux util4vum
[2019-06-19 11:23:45:612 '' 140088508442560 INFO] [installerRunDBCommand, 302] [DATABASE] Upgrade to schema version: 100
[2019-06-19 11:23:45:612 '' 140088508442560 DEBUG] [installerRunDBCommand, 328] [DATABASE] base = ../share/VCI_base_postgresql.sql, proc = ../share/VCI_proc_postgresql.sql, undo = ../share/VCI_undo_postgresql.sql, table upgrade = ../share/VCI_table_postgresql, sp upgrade = ../share/VCI_proc_postgresql, data upgrade = ../share/VCI_data_postgresql, target version = 100
[2019-06-19 11:23:45:613 '' 140088508442560 ERROR] [installerRunDBCommand, 146] [DATABASE] InitConnection: ODBC error: (IM002) - [unixODBC][Driver Manager]Data source name not found, and no default driver specified
[2019-06-19 11:23:45:613 '' 140088508442560 ERROR] [installerRunDBCommand, 331] [DATABASE] Failed to log in db.

Note: The updatemgr-utility.log file is located at:

vCenter Server Appliance: /var/log/vmware/vmware-updatemgr

Environment

VMware vCenter Server Appliance 6.5.x

Cause

The issue occurs when the update manager is not able to reach the VUM database due to ODBC connection failiure.
The error message from the logs says that the ODBC connection to the VUM database cannot be established.

Resolution

To resolve this issue, we need to re-create the odbc.ini file located at /etc/odbc.ini.

Note: Strongly recommended to backup the vCenter Server before following below procedure.

Connect to your vCenter appliance using SSH or console, enter a bash shell..
Stop all the vcenter services by running this command: service-control --stop --all
Edit the odbc.ini file: vi /etc/odbc.ini
Enter insert mode by pressing i, paste the below inside the file :

NOTE : Paste the below in two parts and not in one go :

[VMware VirtualCenter]

;DB_TYPE = PostgreSQL

;SERVER_NAME = localhost

;SERVER_PORT = 5432

;TNS_SERVICE = VCDB

;USER_ID = vc

Application Attributes = T

Attributes = W

BatchAutocommitMode = IfAllSuccessful

BindAsFLOAT = F

CloseCursor = F

DisableDPM = F

DisableMTS = T

Driver = PostgreSQL

DSN = VMware VirtualCenter

EXECSchemaOpt =

EXECSyntax = T

Failover = T

FailoverDelay = 10

FailoverRetryCount = 10

ForceWCHAR = F

Lobs = T

Longs = T

MetadataIdDefault = F

QueryTimeout = T

ResultSets = T

ServerName = localhost

PortNumber = 5432

Server = localhost

Port = 5432

SQLGetData extensions = F

Translation DLL =

Translation Option = 0

DisableRULEHint = T

UserID = vc

User = vc

Database = VCDB

Logging = 0

QuotedId = Yes

AnsiNPW = Yes

Mars_Connection = No

ByteaAsLongVarBinary = 1

BoolsAsChar = 0

UseDeclareFetch = 1

Fetch = 1024

[VUMDSN]