RFC 5907
Definitions of Managed Objects for Network Time Protocol Version 4 (NTPv4)
RFC 5907: Definitions of Managed Objects for Network Time Protocol Version 4 (NTPv4) ✨
Okay bestie, this is RFC 5907 🎀, an IETF document from June 2010. It's on the Standards Track, so it's a real Internet standard and not just vibes 💅. The main author is H. Gerstung from Meinberg, with C. Elliott, and B. Haberman (Ed.) from JHU APL as editor. Its ISSN is 2070-1721 🦋. The header doesn't list any RFC that it obsoletes or updates, so it's standing on its own 👑.
Abstract ✨
NTP is the time-sync system used on every kind of network, from servers and workstations to all sorts of networked gear ⏰. As time sync becomes more mission-critical, operators need standard ways to monitor and manage it, so they can build a monitoring setup that doesn't depend on one platform or one vendor 🫶. This document gives a standard set of data objects for monitoring the NTP entity on a networked host, and it's part of the NTP version 4 standardisation effort 🌈.
Status of This Memo
This is an Internet Standards Track document 🔥.
It's a product of the IETF and reflects what the IETF community agreed on. It went through public review and got approved for publication by the IESG. More about Internet Standards is in Section 2 of RFC 5741 📚.
For the latest status, errata, and ways to send feedback, check http://www.rfc-editor.org/info/rfc5907 🍓.
Copyright Notice
Copyright (c) 2010 IETF Trust and the people listed as the document's authors. All rights reserved 💜.
This document is covered by BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents, at http://trustee.ietf.org/license-info, as they were on the publication date. Please actually read these, because they spell out your rights and restrictions 🙈. Code extracted from this document has to include the Simplified BSD License text, as described in Section 4.e of the Trust Legal Provisions. It comes with no warranty, as the Simplified BSD License describes ✨.
Table of Contents
1. Introduction ....................................................2
2. Conventions Used in This Document ...............................3
3. The Internet-Standard Management Framework ......................3
4. Technical Description ...........................................3
5. MIB Definition ..................................................4
6. IANA Considerations ............................................23
7. Security Considerations ........................................23
8. Acknowledgments ................................................24
9. References .....................................................24
9.1. Normative References ......................................24
9.2. Informative References ....................................21. Introduction 🎀
Okay so the NTPv4 MIB module lets SNMP monitor and manage local NTP [RFC5905] entities 🦋. It's a set of data objects you can query over SNMP, and they show what the NTP entity is doing right now. That covers general info about the entity (vendor, product, version) and how it connects to the upstream NTP servers it takes reference time from, plus hardware reference clocks like radio clocks 📡. The most important values are in there so you can spot failures before they mess with the time sync of the whole network 😭. There are also notification objects that tell you when the NTP entity's state changes, and objects that control those notifications too 💅.
2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be read as described in [RFC2119] 📖✨.
3. The Internet-Standard Management Framework
If you want the full tour of the documents that make up the current Internet-Standard Management Framework, go to section 7 of RFC 3410 [RFC3410] 🗺️.
Managed objects live in a virtual information store called the Management Information Base, or MIB 🗃️. You usually reach MIB objects through the Simple Network Management Protocol (SNMP). The objects are defined with the Structure of Management Information (SMI). This memo's MIB module follows SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580] 💖.
4. Technical Description 🧚
The NTPv4 MIB module is split into sections 🌸. There's general server info, the current status of the NTP entity, the status of every mobilised association (like unicast upstream time servers, multicast or broadcast sources, time references, and hardware clocks), control objects for the NTP entity, NTP objects that only show up in notifications, and the SNMP notification definitions for core events 💜.
The general server info section is static, so you can use it to figure out which NTP implementation is running on a host. It includes the vendor and product name, the version info, the hardware and OS platform, and the time resolution of the underlying OS 🎀.
Section 2 (current NTP status) holds the data objects for the entity's current operational status 🔥.
The third section has the data objects for the set of time references ("associations") the NTP entity is working with right now ⭐.
The fourth section has the objects you use to control the NTP entity. Right now they set how often the heartbeat interval notification goes out and which notifications are turned on 🎛️.
The fifth section only holds objects used as varbinds in notifications. Right now there's just one: a message that adds a cleartext event message to a notification 💬.
Some important events can happen while the NTP entity is running. The notification section defines SNMP notifications for the most important ones (the "core events"). It also has a heartbeat notification and a test notification. The test notification lets management systems check that they're receiving NTP notifications, and the heartbeat lets monitoring systems confirm the NTP entity is still up and running 🫶.
Some values show up in both numeric and human-readable (string) form, which makes the status info easier to read 🌈. If the two forms of a value don't match, the numeric one wins ✨.
5. MIB Definition 👑
-- *********************************************************************
--
-- The Network Time Protocol Version 4
-- Management Information Base (MIB)
--
-- Authors: Heiko Gerstung (heiko.gerstung@meinberg.de)
-- Chris Elliott (chelliot@pobox.com)
--
-- for the Internet Engineering Task Force (IETF)
-- NTP Working Group (ntpwg)
--
--
-- *********************************************************************
-- Rev 1.00
-- Published as RFC 5907
--
-- *********************************************************************
NTPv4-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE , mib-2, Integer32, NOTIFICATION-TYPE,
Unsigned32, Counter32, TimeTicks
FROM SNMPv2-SMI -- RFC 2578
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF -- RFC 2580
DisplayString, TEXTUAL-CONVENTION
FROM SNMPv2-TC -- RFC 2579
InetAddressType, InetAddress
FROM INET-ADDRESS-MIB -- RFC 4001
Utf8String
FROM SYSAPPL-MIB; -- RFC 2287
ntpSnmpMIB MODULE-IDENTITY
LAST-UPDATED "201005170000Z" -- May 17, 2010
ORGANIZATION "The IETF NTP Working Group (ntpwg)"
CONTACT-INFO
" WG Email: ntpwg@lists.ntp.isc.org
Subscribe:
https://lists.ntp.isc.org/mailman/listinfo/ntpwg
Heiko Gerstung
Meinberg Funkuhren Gmbh & Co. KG
Lange Wand 9
Bad Pyrmont 31812
Germany
Phone: +49 5281 9309 25
Email: heiko.gerstung@meinberg.de
Chris Elliott
1516 Kent St.
Durham, NC 27707
USA
Phone: +1-919-308-1216
Email: chelliot@pobox.com
Brian Haberman
11100 Johns Hopkins Road
Laurel, MD 20723
USA
Phone: +1-443-778-1319
Email: brian@innovationslab.net"
DESCRIPTION
"The Management Information Base for NTP time entities.
Copyright (c) 2010 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info)."
REVISION "201005170000Z"
DESCRIPTION
"This revision of the MIB module is published as RFC 5907."
::= { mib-2 197 }
ntpSnmpMIBObjects OBJECT IDENTIFIER ::= { ntpSnmpMIB 1 }
-- MIB contains 6 groups
ntpEntInfo OBJECT IDENTIFIER ::= { ntpSnmpMIBObjects 1 }
ntpEntStatus OBJECT IDENTIFIER ::= { ntpSnmpMIBObjects 2 }
ntpAssociation OBJECT IDENTIFIER ::= { ntpSnmpMIBObjects 3 }
ntpEntControl OBJECT IDENTIFIER ::= { ntpSnmpMIBObjects 4 }
ntpEntNotifObjects OBJECT IDENTIFIER ::= { ntpSnmpMIBObjects 5 }
--
-- Textual Conventions
--
NtpStratum ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"The NTP stratum, with 16 representing no stratum."
SYNTAX Unsigned32 (1..16)
NtpDateTime ::= TEXTUAL-CONVENTION
DISPLAY-HINT "4d:4d:4d.4d"
STATUS current
DESCRIPTION
"NTP date/time on the device, in 128-bit
NTP date format. If time is not syncronized, this
field shall be a zero-length string.
This trusted certificate (TC) is not to be used for objects
that are used to set the time of the node querying this
object. NTP should be used for this -- or at least SNTP."
REFERENCE "RFC 5905, section 6"
SYNTAX OCTET STRING (SIZE (0 | 16))
--
-- Section 1: General NTP Entity information objects
-- (relatively static information)
--
ntpEntSoftwareName OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The product name of the running NTP version, e.g., 'ntpd'."
::= { ntpEntInfo 1 }Okay so the software version object is up next, and it's giving full receipts 🧾✨
ntpEntSoftwareVersion OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The software version of the installed NTP implementation
as a full version string, e.g., 'ntpd-4.2.0b@1.1433 ...'"
::= { ntpEntInfo 2 }
ntpEntSoftwareVendor OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The vendor/author of the installed NTP version."
::= { ntpEntInfo 3 }
ntpEntSystemType OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"General hardware/os platform information,
e.g., 'Linux 2.6.12 / x86'."
-- freely configurable, default is OS Version / Hardware platform
::= { ntpEntInfo 4 }
ntpEntTimeResolution OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The time resolution in integer format, where the resolution
is represented as divisions of a second, e.g., a value of 1000
translates to 1.0 ms."
::= { ntpEntInfo 5 }
ntpEntTimePrecision OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The entity's precision in integer format, shows the precision.
A value of -5 would mean 2^-5 = 31.25 ms."
::= { ntpEntInfo 6 }
ntpEntTimeDistance OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The distance from this NTP entity to the root time reference
(stratum 0) source including the unit, e.g., '13.243 ms'."
::= { ntpEntInfo 7 }ntpEntTimeResolution is the one that's giving math 🧮 because a value of 1000 is 1.0 ms, and ntpEntTimePrecision is the power-of-two version where -5 means 2^-5 = 31.25 ms. Bestie, the way that these two work together is so clean 😭💅
--
-- Section 2: Current NTP status (dynamic information)
--
ntpEntStatusCurrentMode OBJECT-TYPE
SYNTAX INTEGER {
notRunning(1),
notSynchronized(2),
noneConfigured(3),
syncToLocal(4),
syncToRefclock(5),
syncToRemoteServer(6),
unknown(99)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current mode of the NTP. The definition of each possible
value is:
notRunning(1) - NTP is not running.
notSynchronized(2) - NTP is not synchronized to any time
source (stratum = 16).
noneConfigured(3) - NTP is not synchronized and does not
have a reference configured
(stratum = 16).
syncToLocal(4) - NTP is distributing time based on its
local clock (degraded accuracy and/or
reliability).
syncToRefclock(5) - NTP is synchronized to a local
hardware refclock (e.g., GPS).
syncToRemoteServer(6) - NTP is synchronized to a remote
NTP server ('upstream' server).
unknown(99) - The state of NTP is unknown."
::= { ntpEntStatus 1 }
ntpEntStatusStratum OBJECT-TYPE
SYNTAX NtpStratum
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The NTP entity's own stratum value. Should be a stratum of
syspeer + 1 (or 16 if no syspeer)."
::= { ntpEntStatus 2 }
ntpEntStatusActiveRefSourceId OBJECT-TYPE
SYNTAX Unsigned32 ( 0..99999 )
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The association ID of the current syspeer."
::= { ntpEntStatus 3 }
ntpEntStatusActiveRefSourceName OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The hostname/descriptive name of the current reference source
selected as syspeer, e.g., 'ntp1.ptb.de' or 'GPS' or
'DCFi', ..."
::= { ntpEntStatus 4 }
ntpEntStatusActiveOffset OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The time offset to the current selected reference time source
as a string including unit, e.g., '0.032 ms' or '1.232 s'."
::= { ntpEntStatus 5 }
ntpEntStatusNumberOfRefSources OBJECT-TYPE
SYNTAX Unsigned32 (0..99)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of reference sources configured for NTP."
::= { ntpEntStatus 6 }
ntpEntStatusDispersion OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The root dispersion of the running NTP entity, e.g., '6.927'."
::= { ntpEntStatus 7 }
ntpEntStatusEntityUptime OBJECT-TYPE
SYNTAX TimeTicks
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The uptime of the NTP entity, (i.e., the time since ntpd was
(re-)initialized not sysUptime!). The time is represented in
hundreds of seconds since Jan 1, 1970 (00:00:00.000) UTC."
::= { ntpEntStatus 8 }
ntpEntStatusDateTime OBJECT-TYPE
SYNTAX NtpDateTime
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current NTP date/time on the device, in 128-bit
NTP date format. If time is not syncronized, this
field shall be a zero-length string.
This object can be used to timestamp events on this
node and allow a management station to correlate
different time objects. For example, a management
station could query this object and sysUpTime in
the same operation to be able to relate sysUpTime
to NTP time.
This object is not to be used to set the time of
the node querying this object. NTP should be used
for this -- or at least SNTP."
REFERENCE "RFC 5905, section 6"
::= { ntpEntStatus 9 }The ntpEntStatusCurrentMode enum is basically the whole vibe check 🔍 from "not running" all the way to "syncToRemoteServer", and 99 is the "idk bestie" option 💀. Also, ntpEntStatusDateTime is giving timestamp goals ⏰: it's for lining events up against sysUpTime, and it is NOT for setting the clock on the box you're querying. Use NTP for that, or at least SNTP 🙈
ntpEntStatusLeapSecond OBJECT-TYPE
SYNTAX NtpDateTime
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Date the next known leap second will occur. If there is
no leap second announced, then this object should be 0."
::= { ntpEntStatus 10 }
ntpEntStatusLeapSecDirection OBJECT-TYPE
SYNTAX Integer32 (-1..1)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Direction of next known leap second. If there is no
leap second announced, then this object should be 0."
::= { ntpEntStatus 11 }
ntpEntStatusInPkts OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages delivered to the
NTP entity from the transport service.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatus 12 }
ntpEntStatusOutPkts OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages delivered to the
transport service by this NTP entity.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatus 13 }
ntpEntStatusBadVersion OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages that were delivered
to this NTP entity and were for an unsupported NTP
version.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatus 14 }
ntpEntStatusProtocolError OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages that were delivered
to this NTP entity and this entity was not able to
process due to an NTP protocol error.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatus 15 }
ntpEntStatusNotifications OBJECT-TYPE
SYNTAX Counter32
UNITS "notifications"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of SNMP notifications that this NTP
entity has generated.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatus 16 }The leap second objects are giving calendar drama 📅: the date of the next known leap second, plus which direction it goes (-1 to 1). If nothing's announced, both get 0, which is honestly the most chill answer ever 🫶
Then there's the whole counter squad: ntpEntStatusInPkts, ntpEntStatusOutPkts, ntpEntStatusBadVersion, ntpEntStatusProtocolError, and ntpEntStatusNotifications 📦. They all reset on cold start or reinitialization, so keep sysUpTime nearby to read them right 🦋
ntpEntStatPktModeTable OBJECT-TYPE
SYNTAX SEQUENCE OF NtpEntStatPktModeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The number of packets sent and received by packet mode.
One entry per packet mode."
::= { ntpEntStatus 17 }
ntpEntStatPktModeEntry OBJECT-TYPE
SYNTAX NtpEntStatPktModeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A statistical record of the number of packets sent and
received for each packet mode."
INDEX { ntpEntStatPktMode }
::= { ntpEntStatPktModeTable 1 }
NtpEntStatPktModeEntry ::= SEQUENCE {
ntpEntStatPktMode INTEGER,
ntpEntStatPktSent Counter32,
ntpEntStatPktReceived Counter32
}
ntpEntStatPktMode OBJECT-TYPE
SYNTAX INTEGER {
symetricactive(1),
symetricpassive(2),
client(3),
server(4),
broadcastserver(5),
broadcastclient(6)
}
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The NTP packet mode."
::= { ntpEntStatPktModeEntry 1 }
ntpEntStatPktSent OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of NTP packets sent with this packet mode.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatPktModeEntry 2 }
ntpEntStatPktReceived OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of NTP packets received with this packet mode.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpEntStatPktModeEntry 3 }The packet mode table is a whole spreadsheet 📊 with one row per mode, and each row tracks how many packets were sent and how many were received. It's giving organized, and I'm obsessed 😭🌸
--
-- Section 3: The status of all currently mobilized associations
--
ntpAssociationTable OBJECT-TYPE
SYNTAX SEQUENCE OF NtpAssociationEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table of currently mobilized associations."
::= { ntpAssociation 1 }Okay bestie, we're officially in Section 3 now, where the associations get their own spotlight 🎀✨ Stay tuned because it's about to get so iconic 👑
okay so this is the part where each association gets its own row in the table, and the row has all the juicy info 💖 let's go 🦋
ntpAssociationEntry OBJECT-TYPE
SYNTAX NtpAssociationEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table entry of currently mobilized associations."
INDEX { ntpAssocId }
::= { ntpAssociationTable 1 }
NtpAssociationEntry ::= SEQUENCE {
ntpAssocId Unsigned32,
ntpAssocName Utf8String,
ntpAssocRefId DisplayString,
ntpAssocAddressType InetAddressType,
ntpAssocAddress InetAddress,
ntpAssocOffset DisplayString,
ntpAssocStratum NtpStratum,
ntpAssocStatusJitter DisplayString,
ntpAssocStatusDelay DisplayString,
ntpAssocStatusDispersion DisplayString
}
ntpAssocId OBJECT-TYPE
SYNTAX Unsigned32 ( 1..99999 )
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The association ID. This is an internal, unique ID."
::= { ntpAssociationEntry 1 }
ntpAssocName OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The hostname or other descriptive name for the association."
::= { ntpAssociationEntry 2 }
ntpAssocRefId OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The refclock driver ID, if available."
-- a refclock driver ID like "127.127.1.0" for non
-- uni/multi/broadcast associations
::= { ntpAssociationEntry 3 }
ntpAssocAddressType OBJECT-TYPE
SYNTAX InetAddressType { ipv4(1), ipv6(2), ipv4z(3), ipv6z(4) }
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of address of the association. Can be either IPv4 or
IPv6 (both with or without zone index) and contains the type of
address for unicast, multicast, and broadcast associations."
::= { ntpAssociationEntry 4 }
ntpAssocAddress OBJECT-TYPE
SYNTAX InetAddress (SIZE (4|8|16|20))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The IP address (IPv4 or IPv6, with or without zone index) of
the association. The type and size depends on the
ntpAssocAddressType object. Represents the IP address of a
uni/multi/broadcast association."
::= { ntpAssociationEntry 5 }
ntpAssocOffset OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The time offset to the association as a string."
-- including unit, e.g., "0.032 ms" or "1.232 s"
::= { ntpAssociationEntry 6 }
ntpAssocStratum OBJECT-TYPE
SYNTAX NtpStratum
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The association stratum value."
::= { ntpAssociationEntry 7 }
ntpAssocStatusJitter OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The jitter in milliseconds as a string."
::= { ntpAssociationEntry 8 }
ntpAssocStatusDelay OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The network delay in milliseconds as a string."
::= { ntpAssociationEntry 9 }
ntpAssocStatusDispersion OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The root dispersion of the association."
-- e.g., "6.927"
::= { ntpAssociationEntry 10 }
ntpAssociationStatisticsTable OBJECT-TYPE
SYNTAX SEQUENCE OF NtpAssociationStatisticsEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table of statistics for current associations."
::= { ntpAssociation 2 }
ntpAssociationStatisticsEntry OBJECT-TYPE
SYNTAX NtpAssociationStatisticsEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table entry of statistics for current associations."
INDEX { ntpAssocId }
::= { ntpAssociationStatisticsTable 1 }
NtpAssociationStatisticsEntry ::= SEQUENCE {
ntpAssocStatInPkts Counter32,
ntpAssocStatOutPkts Counter32,
ntpAssocStatProtocolError Counter32
}
ntpAssocStatInPkts OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages delivered to the
NTP entity from this association.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpAssociationStatisticsEntry 1 }
ntpAssocStatOutPkts OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages delivered to the
transport service by this NTP entity for this
association.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpAssociationStatisticsEntry 2 }
ntpAssocStatProtocolError OBJECT-TYPE
SYNTAX Counter32
UNITS "packets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of NTP messages that were delivered
to this NTP entity from this association and this entity
was not able to process due to an NTP protocol error.
Discountinuities in the value of this counter can occur
upon cold start or reinitialization of the NTP entity, the
management system and at other times as indicated by
discontinuities in the value of sysUpTime."
::= { ntpAssociationStatisticsEntry 3 }4. Control objects ✨
this section is where you get to control the NTP entity, like setting how often the heartbeat goes off and which notifications are switched on 🎀 the settings are stored persistently, so they survive a cold start or restart 🧚
--
-- Section 4: Control objects
--
ntpEntHeartbeatInterval OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"The interval at which the ntpEntNotifHeartbeat notification
should be sent, in seconds. If set to 0 and the
entNotifHeartbeat bit in ntpEntNotifBits is 1, then
ntpEntNotifHeartbeat is sent once.
This value is stored persistently and will be restored to its
last set value upon cold start or restart."
DEFVAL { 60 }
::= { ntpEntControl 1 }
ntpEntNotifBits OBJECT-TYPE
SYNTAX BITS {
notUsed(0), -- Used to sync up bit and notification
-- indices
entNotifModeChange(1),
entNotifStratumChange(2),
entNotifSyspeerChanged(3),
entNotifAddAssociation(4),
entNotifRemoveAssociation(5),
entNotifConfigChanged(6),
entNotifLeapSecondAnnounced(7),
entNotifHeartbeat(8)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A bit for each notification. A 1 for a particular bit enables
that particular notification, a 0 disables it.
This value is stored persistently and will be restored to its
last set value upon cold start or restart."
::= { ntpEntControl 2 }5. Notification objects ✨
okay now the notifications get their own payload object 📣 this is the cleartext message that rides along with every single one of them 💌
--
-- Section 5: Notification objects
--
ntpEntNotifMessage OBJECT-TYPE
SYNTAX Utf8String
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"Used as a payload object for all notifications. Holds a
cleartext event message."
DEFVAL { "no event" }
::= { ntpEntNotifObjects 1 }SNMP notification definitions 🦋
--
-- SNMP notification definitions
--
ntpEntNotifications OBJECT IDENTIFIER ::= { ntpSnmpMIB 0 }
ntpEntNotifModeChange NOTIFICATION-TYPE
OBJECTS { ntpEntStatusCurrentMode }
STATUS current
DESCRIPTION
"The notification to be sent when the NTP entity changes mode,
including starting and stopping (if possible)."
::= { ntpEntNotifications 1 }
ntpEntNotifStratumChange NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpEntStatusStratum,
ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when stratum level of NTP changes."
::= { ntpEntNotifications 2 }
ntpEntNotifSyspeerChanged NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpEntStatusActiveRefSourceId,
ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when a (new) syspeer has been
selected."
::= { ntpEntNotifications 3 }
ntpEntNotifAddAssociation NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpAssocName, ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when a new association is
mobilized."
::= { ntpEntNotifications 4 }
ntpEntNotifRemoveAssociation NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpAssocName, ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when an association is
demobilized."
::= { ntpEntNotifications 5 }
ntpEntNotifConfigChanged NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when the NTP configuration has
changed, e.g., when the system connected to the Internet and
was assigned a new IP address by the ISPs DHCP server."
::= { ntpEntNotifications 6 }
ntpEntNotifLeapSecondAnnounced NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent when a leap second has been
announced."
::= { ntpEntNotifications 7 }
ntpEntNotifHeartbeat NOTIFICATION-TYPE
OBJECTS { ntpEntStatusDateTime, ntpEntStatusCurrentMode,
ntpEntHeartbeatInterval, ntpEntNotifMessage }
STATUS current
DESCRIPTION
"The notification to be sent periodically (as defined by
ntpEntHeartbeatInterval) to indicate that the NTP entity is
still alive."
::= { ntpEntNotifications 8 }Conformance/Compliance statements 🌈
--
-- Conformance/Compliance statements
--
ntpEntConformance OBJECT IDENTIFIER ::= { ntpSnmpMIB 2 }
ntpEntCompliances OBJECT IDENTIFIER ::= { ntpEntConformance 1 }
ntpEntGroups OBJECT IDENTIFIER ::= { ntpEntConformance 2 }
ntpEntNTPCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP entities that use NTP and
implement the NTP MIB."
MODULE -- this module
MANDATORY-GROUPS {
ntpEntObjectsGroup1
}
::= { ntpEntCompliances 1 }
ntpEntSNTPCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP entities that use SNTP and
implement the NTP MIB."
MODULE -- this module
MANDATORY-GROUPS {
ntpEntObjectsGroup1
}
GROUP ntpEntObjectsGroup2
DESCRIPTION
"Optional object group."
GROUP ntpEntNotifGroup
DESCRIPTION
"Optional notifications for this MIB."
::= { ntpEntCompliances 2 }ntpEntObjectsGroup1 OBJECT-GROUP
OBJECTS {
ntpEntSoftwareName,
ntpEntSoftwareVersion,
ntpEntSoftwareVendor,
ntpEntSystemType,
ntpEntStatusEntityUptime,
ntpEntStatusDateTime,
ntpAssocName,
ntpAssocRefId,
ntpAssocAddressType,
ntpAssocAddress
}
STATUS current
DESCRIPTION
"A collection of objects for the NTP MIB."
::= { ntpEntGroups 1 }
ntpEntObjectsGroup2 OBJECT-GROUP
OBJECTS {
ntpEntTimeResolution,
ntpEntTimePrecision,
ntpEntTimeDistance,
ntpEntStatusCurrentMode,
ntpEntStatusStratum,
ntpEntStatusActiveRefSourceId,
ntpEntStatusActiveRefSourceName,
ntpEntStatusActiveOffset,
ntpEntStatusNumberOfRefSources,
ntpEntStatusDispersion,
ntpEntStatusLeapSecond,
ntpEntStatusLeapSecDirection,
ntpEntStatusInPkts,
ntpEntStatusOutPkts,
ntpEntStatusBadVersion,
ntpEntStatusProtocolError,
ntpEntStatusNotifications,
ntpEntStatPktSent,
ntpEntStatPktReceived,
ntpAssocOffset,
ntpAssocStratum,
ntpAssocStatusJitter,
ntpAssocStatusDelay,
ntpAssocStatusDispersion,
ntpAssocStatInPkts,
ntpAssocStatOutPkts,
ntpAssocStatProtocolError,
ntpEntHeartbeatInterval,
ntpEntNotifBits,
ntpEntNotifMessage
}
STATUS current
DESCRIPTION
"A collection of objects for the NTP MIB."
::= { ntpEntGroups 2 }
ntpEntNotifGroup NOTIFICATION-GROUP
NOTIFICATIONS {
ntpEntNotifModeChange,
ntpEntNotifStratumChange,
ntpEntNotifSyspeerChanged,
ntpEntNotifAddAssociation,
ntpEntNotifRemoveAssociation,
ntpEntNotifConfigChanged,
ntpEntNotifLeapSecondAnnounced,
ntpEntNotifHeartbeat
}
STATUS current
DESCRIPTION
"A collection of notifications for the NTP MIB"
::= { ntpEntGroups 3 }
END6. IANA Considerations 🌸
The MIB module in this document uses the following IANA-assigned OBJECT IDENTIFIER values recorded in the SMI Numbers registry:
Descriptor OBJECT IDENTIFIER value
---------- -----------------------
ntpSnmp { mib-2 197 }7. Security Considerations 💀
Okay bestie, this part is SERIOUS 😭 There are currently two management objects defined in this MIB module with a MAX-ACCESS clause of read-write and/or read-create. Those objects may be considered sensitive or vulnerable in some network environments. SET operations in a non-secure environment without proper protection can have a negative effect on network operations. Here are the objects and why they're sensitive:
ntpEntHeartbeatInterval controls the interval of heartbeat notifications. If you set it to 1, the NTP entity sends one notification each second, which is the maximum automatic rate (1/s). If you set it to 0, you get one single heartbeat notification and no further automatically generated ones. This trick can be used to create notifications at a higher rate, as high as the object can be written. 🚨
ntpEntNotifBits enables and disables notifications. It could be used to switch them off in order to delay or eliminate notifications for critical and important events. 🙈
Some of the readable objects in this MIB module (objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. So it's important to control even GET and/or NOTIFY access to these objects, and possibly even encrypt their values when sending them over the network via SNMP. Here are the tables and objects and why they matter:
ntpEntSoftwareName, ntpEntSoftwareVersion, ntpEntSoftwareVendor, and ntpEntSystemType can all be used to identify software and its version, as well as the operating system and hardware platform. This might help a potential attacker find security problems, and therefore can be used in the preparation of an attack. 👀
SNMP versions prior to SNMPv3 did not include adequate security. Even if the network itself is secure (for example by using IPsec), there is still no control over who on that secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB module. It is RECOMMENDED that implementers consider the security features provided by the SNMPv3 framework (see RFC 3410 [RFC3410], section 8), including full support for the SNMPv3 cryptographic mechanisms (for authentication and privacy). Further, deployment of SNMP versions prior to SNMPv3 is NOT RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to enable cryptographic security. It is then a customer/operator responsibility to ensure that the SNMP entity giving access to an instance of this MIB module is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them. 🔐
8. Acknowledgments 🫶
Bert Wijnen provided valuable feedback as the MIB Doctor for this document. Thank you, Bert! 💖
9. References 📚
9.1. Normative References
- [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
- [RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch, "Network Time Protocol Version 4: Protocol and Algorithms Specification", RFC 5905, June 2010.
- [RFC2287] Krupczak, C. and J. Saperia, "Definitions of System-Level Managed Objects for Applications", RFC 2287, February 1998.
- [RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
- [RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999.
- [RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999.
- [RFC4001] Daniele, M., Haberman, B., Routhier, S., and J. Schoenwaelder, "Textual Conventions for Internet Network Addresses", RFC 4001, February 2005.
9.2. Informative References
- [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet-Standard Management Framework", RFC 3410, December 2002.
Authors' Addresses 🎀
Heiko Gerstung
Meinberg Funkuhren Gmbh & Co. KG
Lange Wand 9
Bad Pyrmont 31812
Germany
Phone: +49 5281 9309 25
EMail: heiko.gerstung@meinberg.deChris Elliott
1516 Kent St.
Durham, NC 27707
USA
Phone: +1-919-308-1216
EMail: chelliot@pobox.comBrian Haberman (editor)
Johns Hopkins University Applied Physics Lab
11100 Johns Hopkins Road
Laurel, MD 20723-6099
US
Phone: +1 443 778 1319
EMail: brian@innovationslab.net📦 where this page comes from
- ietf: rfc5907 2010-06
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms