Contents

1   Overview

1.1   Description

This alarm is raised when there is no communication with a remote Ericsson Centralized User Database (CUDB) site.

The alarm attributes are listed and explained in Table 1.

Table 1    Alarm Attributes

Attribute Name	Attribute Value
Auto Cease	Yes
Module	CONTROL
Error Code	3
Timestamp First	Date and time when the alarm was raised for the first time.
Repeated Counter	Number which indicates how many times the alarm was raised.
Timestamp Last	Date and time of the most recent alarm raise.
Resource ID	.1.3.6.1.4.1.193.169.7.3.<SI>
Alarm Model Description	Remote CUDB Site Unreachable, Control.
Alarm Active Description	Control: CUDB site <SI> unreachable
ITU Alarm Event Type	communicationsAlarm (2)
ITU Alarm Probable Cause	communicationSubsystemFailure (505)
ITU Alarm Perceived Severity	(3) - Critical
Originating source IP	Node IP where the alarm was raised.
Sequence Number	Number which indicates the order in which the alarms are raised.

In Table 1, the indicated variables are as follows:

• <SI> is the identifier of the non reachable CUDB Site (refer to CUDB Node Configuration Data Model Description, Reference [1], for further information).

For further information about fields description refer to CUDB Node Fault Management Configuration Guide, Reference [2].

The possible causes are as follows:

• Network outages.
• Blackboard Coordination (BC) cluster is down in the remote site.
• CUDB node failure or multiple node failures.

1.2   Prerequisites

1.2.1   Documents

Refer to CUDB System Administrator Guide, Reference [3], for further information.

1.2.2   Tools

Not applicable.

1.2.3   Conditions

Not applicable.

2   Procedure

Perform the following steps:

1. Check if additional sites have raised the Control, Remote CUDB Site Unreachable alarm referring to the non reachable site. If not, this means that the unreachable site is not down, and the failure could be due to a network connection towards that site. Check the network connections and fix them. The case of network connection failures is out of the scope of this Operating Instruction.
2. Check if Control, Blackboard Coordination Cluster Down alarm is raised at the unreachable site. If so, follow the procedure depicted in Operating Instruction describing this alarm (Control, Blackboard Coordination Cluster Down, Reference [4]).
3. Check if Control, Potential Split Brain Detected alarm is raised. If so, follow the procedure depicted in Operating Instruction describing this alarm (Control, Potential Split Brain Detected, Reference [5]).
4. Try to connect offline (for example from external system) to one node of the unreachable site or use other measures in order to distinguish if it is a network problem. If the failure comes from the network, further actions are outside the scope of this Operating Instruction.
5. Check for possible infrastructure problems related to the communication between CUDB nodes (in switches, network connections, and so on), and fix them.
6. If alarm does not cease, consult the next level of maintenance support.

Glossary

For the terms, definitions, acronyms and abbreviations used in this document, refer to CUDB Glossary of Terms and Acronyms, Reference [6].

Reference List

CUDB Documents
[1] CUDB Node Configuration Data Model Description.
[2] CUDB Node Fault Management Configuration Guide.
[3] CUDB System Administrator Guide.
[4] Control, Blackboard Coordination Cluster Down.
[5] Control, Potential Split Brain Detected.
[6] CUDB Glossary of Terms and Acronyms.