More on Standby
"David T. Perkins" <[email protected]> Fri, 13 Feb 2004 00:04:29 -0800
| Newsgroups | gmane.ietf.entmib |
|---|---|
| Message-ID | <[email protected]> |
HI,
Here is a replacement for TC StandbyStatus:
StandbyState ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
" Represents the possible values of standby state.
The value 'notAvailable(1)' means that
no information is available on the standby state
for the entity.
The value 'hotStandby(2)' means the entity is not
providing service, and will be immediately able to
start providing service for the entity being backed up
without the need for initialization activity, and will
contain the same information as the entity being
backed up.
The value 'coldStandy(3)' means the entity is not
providing service, and will be able to start providing
service for an entity (possibly one from a set) being
backed up, and will require some initialization
activity.
The value 'providingService(4)' means the
entity is providing service.
The value 'providingSharedService(5)' means the entity
is providing service that is summed with the service
provided by other entities."
REFERENCE
"ITU Recommendation X.731, 'Information Technology - Open
Systems Interconnection - System Management: State
Management Function', 1992"
SYNTAX INTEGER
{
notAvailable(1),
hotStandby(2),
coldStandby(3),
providingService(4),
providingSharedService(5)
}
And a replacement for entStateStandby:
entStateStandby OBJECT-TYPE
SYNTAX StandbyStatus
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The standby state for this entity. A value of
'notAvailable' means that this entity is unable to
determine standby state.
Some entities will exhibit only a subset of the
remaining standby state values. If this entity
cannot operate in a standby role, then the value
with always be 'providingService'."
::= { entStateEntry 6 }
>Date: Thu, 12 Feb 2004 23:41:02 -0800
>To: "Sharon Chisholm" <[email protected]>, [email protected]
>From: "David T. Perkins" <[email protected]>
>Subject: Standby
>
>HI,
>
>"Standby status" items should be renamed to "standby state" to be
>consistent with the other naming of other items in the MIB module.
>(Items are "state" when value is an enumerated int, and "status"
>when the value is a bit string.)
>
>There is one important value missing from the enums for standby.
>It is the one that means that the service output is combined
>with other entities. This is commonly found with power supplies
>where the output is "summed".
>
>Section 2.2 is incorrect. It implies that by reading the value
>of entStandbyStatus for all entities, then entities can be classified
>as redundant (or protected). This is not true. Say that there
>are two entities that are identical and provide a "protected"
>service. At any time, only one is providing service, and the
>other is standing by protecting the other. A "protection switch"
>causes the roles to change (that is the one providing service
>will switch to standing by, and the one standing by will start
>to providing service).
>
>In general, this MIB module does not provide enough information
>to determine 1) which entities are protected, 2) the relationship
>between the entities that are protected and the entities providing
>protection.
>
>Regards,
>/david t. perkins
/david t. perkins