1. NTPV3 – Time Synchronization Service
Siddharth (Siddharth Jagtiani)

2. Highlights Why Time Synchronization ? How Time Synchronization ?
NTPv3 Utilities and LAB
Authentication Options
Backward Compatibility options Why and How
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

3. WHY Time Synchronization ?
11:01
11:00
11:00
11:01
UPDATE
SYNC
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

4. How Time Synchronization ?
Time Request t3
Time Reply t4 t5 t6
Time Request t7
Time Reply t8
Time Consumer
Time Provider
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

5. How Time Synchronization ? Time Exchange
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

6. How Time Synchronization ? Time Exchange - Eg
Offset = ((t2-t1) + (t3-t4)) /2 = 1 min
Delay = (t4-t1) - (t3-t2) = 20 sec
t3-t2 = Zero NetWare OS Non-preemptive scheduling.
Time taken for Request = Time taken for Reply= 10 sec
Time taken to process packet at Time Server = 5 sec
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

7. OS Clock - Interface Time Provider Time Consumer Timesync/ NTPv3
Time Exchange
Time
Consumer
Timesync/
NTPv3
Applications
Write
Correction
Registers
Read
Write
Time
CLOCK Status
Timer
Interrupt
Write
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

8. OS Clock - How © 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

9. Time Correction on OS ? Slam - Correct the clock (NOW !!)
Local Clock = Local Clock + Offset
Slew - Slowly correct the clock (I am in no hurry !!)
Slewed Offset = Offset/Duration of Slew
For (Every second until Duration of Slew)
Local Clock = Local Clock + 1 second + Slewed Offset
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

10. Timesync Slam Vs Slew NOT in Sync Get Time From Time Source
First Time ?
Slew No
Slam
Yes
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

11. Filter/Selection Algorithm
NTPv3 Slam Vs Slew
XNTPD
NTPDate
Get Time
From Time Source
Get Time
From Time Source
Slam
Filter/Selection Algorithm
Slew
OS Clock
Nearly In Sync
OS Clock
In Sync
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

12. Value of NTPv3 Open Source port. RFC 1305
Uniformity between other platforms
NetWare 6.5 includes
Time Synchronization Daemon : xntpd.nlm
Utilities : ntpdate, ntpq, ntptrace and xntpdc
Browser based configuration through NORM
Backward compatibility to service NCP time requests
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

13. NTPv3 Tools in NetWare 6.5 - NTPDATE
Used to slam the time provider’s time on the server.
Helps to achieve synchronization faster.
Similar to timesync’s “Set Clock to first network time”
Time Consumer
Time Provider
Request
123
NtpDate Server B
XNTPD
Reply
OS Clock
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

14. NTPDATE - Options
Usage : [-bBdqsv] [-a key#] [-e delay] [-k file] [-p samples] [-o version#] [-r rate] [-t timeo] server
-b : Step the time without limits
-u : Don’t use port 123
-d -q : only display the time offset
-s : Log actions to file
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

15. NTPDATE - LAB
Tasks
Use NTPDATE to set the time of the server to NTP.NOVELL.COM
Use NTPDATE to set the time to a Timesync Single Server
Load XNTPD and then try to use NTPDATE to set time to NTP.NOVELL.COM
Load Timesync and then try to use NTPDATE to set time to NTP.NOVELL.COM
Use NTPDATE to find out how far you are from NTP.NOVELL.COM, but do NOT set the system time.
Log NTPDATE screen info to file
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

16. NTPv3 Tools in NetWare 6.5 - XNTPD
Maintains synchronized time as long as the server is running
Used to slew the clock with the time provider’s clock
Sys:\etc\ntp.cfg is the default configuration file
Ntp.cfg comes with a lot of examples for helping configuration
-T options help migrate/provide backward compatibility for NCP clients
Ntp configuration on NORM
Health Monitor on NORM
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

17. Sample XNTPD Progress Screen
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

18. XNTPD Manual Configuration
This configuration is similar to “Timesync Configured Sources=ON”
Server can be self synchronized
Time Provider – LOCAL Clock
Server can rely on another server for time.
Time Provider – Another NTP server
Advertise its service (broadcast mode)
Listen to advertisements (broadcastlisten mode)
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

19. Manual Configuration – NTP.Cfg Commands
Local Clock Setup
server [minpoll <4-16>] – Local Clock
fudge stratum <0-15> - Stratum
Time Provider – Another NTP Server
server <ipa/dns name> [minpoll <4-16>] – Time Provider
Poll Delay
minpoll <4-16> - Poll Delay = 2minpoll
5 successful poll’s gets the server to synchronized state
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

20. Manual Configuration – Example
Self Synchronized
IP Address for identifying the local clock –
Used along with the fudge, minpoll and stratum command
Eg :
server minpoll 4
fudge stratum 2
Configure to Take time from another server
IP Address/DNS name of the time provider
Can be used along with minpoll command to increase speed of configuration
server <ipa/dns name> minpoll 4
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

21. NTPv3 Tools in NetWare 6.5 - NTPQ
Query tool to monitor the status and quality of time
Delay
Offset
Error
Progress of synchronization
filt values
Ability to query other NTPv3 servers from a central place
host
Ability to check the status of all your time providers
peers
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

22. NTPQ – Monitoring Commands
associations (as) – List all the associations.
peers (pe) – List the status of each peer
rv <assocID> - List all the variables for the association <assocID>
rvi <index> - List all the variables for the association number <index>
host <ipa>|<dns name> - Change the query server.
showipconf – Show the ipa and broadcast address of this server. (does not work in host mode).
Authentication – Query requests should be encrypted
authenticate [yes|no] – enable/disable authentication
keyid – identity of the client
keytype – type of authentication
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

23. XNTPD / NTPQ - LAB
Tasks
Use XNTPD to configure to use NTP.NOVELL.COM as the time source
Check synchronization status at regular interval’s
Experiences ????
Configure XNTPD to use the server next to you as the time source
Check the synchronization status at regular interval’s
Experiences ????
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

24. Manual Configuration - LAB
Tasks
Configure with multiple time provider using DNS/IP Address
Experiences ?????
Configure a time consumer to synchronize within a minute
Experiences ?????
Configure NTPDATE to run automatically before XNTPD
Set the Time provider’s time ahead by a hour.
Set the Time provider’s time behind by a hour
Experiences ?????
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

25. Manual Configuration LAB – For Experts
Tasks
Use XNTPD to configure to use a NetWare box with Timesync loaded as the time source
Configure XNTPD to help ensure that only “authenticated” clients make time requests
AUTHENTICATION
Configure XNTPD to use Timesync SINGLE server in the tree as your time source.
Configure Timesync to take time from XNTPD in NTP/NCP mode
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

26. NTPQ – LAB – For Experts NTPQ
Configure XNTPD to take time from multiple time providers.
Check the status of all time providers in list at regular interval’s
Experiences ????
Send authenticated requests to the server next to you and monitor the status
Comment on the time providers of the server next to you
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

27. NTPQ Reference How to Configure Time Synchronization Service on Unix ?
8) Some of the important outputs of the “peers” command is detailed as below.
A) First character -
‘+’ ,‘*’ or ‘o’ means - Selected for Synchronization.
‘-’, ‘SPACE’ or ‘#’ means - Discarded.
B) IPA of the Time Source
C) Type or Source - E.g GPS or some other type of Time Source.
D) Stratum
E) Type of peer - Unicast, Multicast, Broadcast or Local.
F) Delay - Round trip delay
G) Offset - Time difference.
E.g for NTPQ-Peers Cmd:
remote refid st t when poll reach delay offset disp
===================================================================
GPS u
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

28. XNTPD Auto Configuration
This configuration is similar to “Timesync Auto Discovery”
Configure the Time Provider to Broadcast its service on the network
Configure the Time Consumers to listen to the broadcast service and synchronize.
Time Provider
broadcast <broadcast address>
Time Consumers
broadcastclient
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

29. Auto Configuration - LAB
Tasks
Configure your server to broadcast its service to the other servers on the network.
Configure your server to accept broadcast’s and listen
Configure your server with authentication to broadcast its service
Configure your server to accept broadcast’s only in authenticated mode
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

30. XNTPD - Authentication Process Request Process
Time Consumer
Time Request
Encrypt
Time Request + Encrypted [Time Request]
Send
Time Provider
Split
Time Request
Encrypted [Time Request]
Discard
Unauthentic
Encrypt
Process Reply
Not Equal
Equal
Compare
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

31. XNTPD - Authentication Process Reply Process
Time Provider
Time Reply
Encrypt
Time Reply + Encrypted [Time Reply]
Send
Time Consumer
Split
Time Reply
Encrypted [Time Reply]
Discard
Unauthentic
Encrypt
Step/Slew
Not Equal
Equal
Compare
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

32. XNTPD – Authentication Setup
Need
Time Consumers need to know if they are contacting the Time Provider they intend to (XNTPD.NLM)
Queries between hosts, need encryption (NTPQ.NLM)
Remote Configuration commands need to come from authenticated clients (XNTPDC.NLM)
NTP.CFG
Key file
Trusted Key - XNTPD.NLM
Request Key – NTPQ.NLM
Control Key – XNTPDC.NLM
server, peer, broadcast – command use the key ID
NTP.KEY
Key ID – Key Identifier
Key Value – Password
Key Type – Encryption method MD5/DES
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

33. XNTPD – Authentication Setup
Time Provider
Share common symmetric key’s between NTP server and NTP client
Eg NTP.KEY
# Key ID Key Type Key Value
M netware_is_the_best
Enable the 420 key as a trusted
Eg : NTP.CFG
keys sys:\etc\ntp.key
trustedkey 420
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

34. XNTPD – Authentication Setup
Time Consumer
Share common symmetric key’s between the NTP server and client
Eg NTP.KEY
# Key ID Key Type Key Value
M netware_is_the_best
NTP client should enable the keys for synchronization
Eg NTP.CFG
Keys sys:\etc\ntp.key
Trustedkey 420
NTP client needs to specify the key that needs to be used for every NTP server
Eg NTP.CFG
server <ntp_server_ip_address> key 420
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

35. XNTPD - Authentication - LAB
Tasks
Configure your server as a time consumer to the server on your right hand side only with authentication
Configure your server as a time provider to the server on your left hand side and provide authentication options
Experiences ???
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

36. XNTPDC Authentication
Need
XNTPDC client needs to have authentic access to modify configuration on the remote server.
Remote server should be able to able to deny access
How
XNTPDC client need to provide the correct keyID, keyValue (password)
Remote server should be able to authenticate a configuration request.
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

37. Authentication Options Remote Configuration Authentication
XNTPDC
Enable authentication option for the server that needs to be Remotely configured.
Insert a entry into ntp.key
Mark the key as controlkey in ntp.cfg
Restart xntpd.nlm
Remote Configure a server - xntpdc
Passwd – Authenticate to the remote server
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

38. NTPQ Authentication Options
Setup the host server
Insert a entry into ntp.key
Mark the key as requestkey in ntp.cfg
Restart xntpd.nlm
Configure Query Client
Insert the key of the time provider in ntp.key
Mark the key as trustedkey in ntp.cfg
Add option “key <keyid>” in ntp.cfg “server” command line
Eg : server <ipaddress> minpoll <vlaue> key <keyid>
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

39. Advanced Configuration
Minimize Traffic
Select servers across geographic locations to be peers to each other – Similar to “Timesync Primary Servers” – This helps in minimizing traffic across WAN’s
Fault Tolerance
Have all these servers use a reference clock (external) as a master server – This helps in fault tolerance.
COMMON - Time Consumer Setup
Have all Time Consumers use one of the above peer servers as a Time provider for itself.
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

40. Advanced Configuration – Lab Minimize Traffic
Self Synchronized
Stratum 10
External
NTP Source
Self Synchronized
Stratum 10
Provo
India
Peer Synchronized
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

41. Advanced Configuration – Lab Fault Tolerance
External
NTP Source
External
NTP Source
Self Synchronized
Stratum 10
Provo
Self Synchronized
Stratum 10
India
Peer Synchronized
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

42. NTPTrace - LAB NTPTrace
Query all servers in the stratum thread to the root (startum 1)
LAB
Query your stratum thread
Experiences ?????
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

43. Extra features for NetWare 6.5
Browser Based configuration (Embedded in xntpd.nlm)
On NORM scroll down to NTP Configuration and click “Manual Configuration”
Modify NTP Configuration file’s, Save, Restart and Apply (save and restart xntpd to reflect new changes)
NTP Version independence
Timesync Migration/Backward Compatibility options
Xntpd –T noncp : Will disable the ncp engine on xntpd. XNTPD will not serve ncp time request’s from NetWare 4.x and Novell Clients
Xntpd –T slp : Will look up SLP for a Timesync SINGLE server on the network, add the Timesync SINGLE server’s IP Address in the ntp.cfg as a time provider
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

44. NTP State Machine NOT Loaded/Not Synchronized Load XNTPD
Loaded/Nearly Synchronized
Step Clock is
Enabled No
Yes
Slew
NTPDATE –u –b <server list from ntp.cfg>
Loaded/Synchronized
NTPDATE
Success
Yes No
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

45. Migration Timesync to NTPv3
Reference – Primary
Primary - Secondary
Reference – Secondary
Secondary – Secondary
Client – Server Manual Configuration
Single – Secondary
Broadcast/Multicast – Broadcastlisten Configuration
Primary – Primary
Peer Configuration
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

46. Backward Compatibility - Problem
NCP Request
NCP Request
BOOM
BOOM
NCP Reply
NCP Reply
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

47. Backward Compatibility – Solution
With NTPv3 and NCP Server
NCP Request
NCP Request
NCP Reply
NCP Reply
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

48. Backward Compatibility – LAB NORM - Lab
Task
Configure NetWare 4.x server to use NetWare 6.5 as a time source
Tasks
Configure your server using NORM, using any configuration mode
Monitor its synchronization status using “Health Monitor”
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

49. Browser based administration - NORM
NTP Configuration
Click on “NTP Configuration” link under “Manage Applications”
Click on the set of servers that you want to configure
Edit the configuration file
Save – saves the contents of the ntp.cfg
Restart – reload xnptd.nlm
Apply – save and restart
NTP Monitoring
Click on “Health Monitor”
Click on “NTP Monitoring Service”
Click on the set of servers that you want to monitor
peers : output same as ntpq
associations : output same as as command on ntpq
variables : output same as “rv <assId>”
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

50. Future for NTPv3 Simplifying NTP/Timesync configuration
More on integrating Timesync backward compatibility with NTPv3 configuration
Cross platform solution – OS Independent
Extending features for helping debugging of time synchronization problems
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018

51. Q & A

52. How Time Synchronization ?
Time Consumer
Time Provider
Time Exchange
NTPv3/Timesync
Read
Write
OS Clock
Read
Time Critical
Applications
© 2002 Novell Inc, Confidential & Proprietary
November 17, 2018