Logging in to vCenter Server Appliance 6.5 fails with the error: Unable to authenticate user. Please try again.

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• Virtual Appliance Management Interface (VAMI) login using <https://VC_FQDN/IP:5480> fails for "root" user with following error:
  • Unable to authenticate user. Please try again
• Login to SSH is successful for "root" user.
• Sample log snippet in /var/log/vmware/applmgmt/vami.log

  YYYY-MM-DD HH:MM:SS [53107]ERROR:session_management:Session Available check failed: No JSON object could be decoded
  Traceback (most recent call last):
    File "/opt/vmware/share/htdocs/vami/backend/session_management.py", line 113, in sessionsAvailable
      cls.expiredSession(ConfigManager(f))):
    File "/usr/lib/applmgmt/base/py/vmware/vherd/base/config_manager.py", line 25, in __init__
      object_hook=lambda d: defaultdict(ConfigManager.defaultFactory, d))
    File "/usr/lib/python2.7/json/__init__.py", line 291, in load
      **kw)
    File "/usr/lib/python2.7/json/__init__.py", line 352, in loads
      return cls(encoding=encoding, **kw).decode(s)
    File "/usr/lib/python2.7/json/decoder.py", line 364, in decode
      obj, end = self.raw_decode(s, idx=_w(s, 0).end())
    File "/usr/lib/python2.7/json/decoder.py", line 382, in raw_decode
      raise ValueError("No JSON object could be decoded")
  ValueError: No JSON object could be decoded
  YYYY-MM-DD HH:MM:SS [53107]ERROR:root:Structure('LocalizableMessage', dict(defaultMessage='The maximum number of sessions has been reached', args=[], id='com.vmware.applmgmt.admind.authenticate.max.session'))

   

Cause

This is caused by a file corruption in the following location of the vCenter Server:

/var/vmware/applmgmt/session/XXXX

Resolution

The issue is fixed in version 6.5 U2.

The following workaround can be followed for versions lower than that:

• Delete all the files in the following location of the vCenter Server:

  /var/vmware/applmgmt/session/

• Reload the VAMI page and try to login using "root" credentials.