ASR 9000 PTP Multicast

[Stephen Craven]

We're trying to configure our ASR 9006 as a PTP slave from a Tekron GPS clock. However, the clock sends multicast PTP announcements and we have been unable to configure our ASR to acknowledge them.

The ASR sends an unicast "Request Unicast Transmission" signalling message to which the clock responds with a multicast "Grant Unicast Transmission" message. The ASR never follows up with a unicast transmission.

PCAP file [cloudshark] -- Router at 192.168.66.10, Clock at .100

In the configuration below we attempt to set the master as multicast in the global PTP configuration. If we try to add the master statement on the interface we get a configuration error stating "Multicast is not supported on this card: Failed to verify the multicast value". The card is an A9K-4T16GE-TR.

ptp
 profile tp64
  transport ipv4
  master ipv4 192.168.66.100
   multicast
  !
  sync frequency 64
  delay-request frequency 64
 !
 log
  best-master-clock changes
 !
!

interface GigabitEthernet0/0/0/2
 ptp
  profile tp64
  transport ipv4
  port state slave-only
  announce timeout 2
 !
 ipv4 address 192.168.66.10 255.255.255.0
 transceiver permit pid all
!

Does our line card support multicast PTP? There doesn't appear to be a way to make our clock send unicast, so we're hoping we can get the router to respond.

Thank you,

Stephen

[Hamam Ismail]

Hello Stephen,

Is this a lab or production device? On the surface the configuration appears correct.

I would like to get more information:

1- show install active sum

2- show platform

3- 2 x show interface GigabitEthernet0/0/0/2 -> while the profile is applied and issue is occurring

[Stephen Craven]

This is a lab install to validate our clocking scheme before we deploy it.

I interpreted #3 as a 'sh int' at two different times. If this is not what you need, please let me know.

Thanks!

Stephen

RP/0/RSP0/CPU0:LAB#Show install active summary
Fri Oct 23 12:25:24.725 EDT
Default Profile:
  SDRs:
    Owner
  Active Packages:
    disk0:asr9k-mini-px-5.3.1
    disk0:asr9k-mpls-px-5.3.1
    disk0:asr9k-k9sec-px-5.3.1
 

RP/0/RSP0/CPU0:LAB#show platform
Fri Oct 23 12:25:43.493 EDT
Node            Type                      State            Config State
-----------------------------------------------------------------------------
0/RSP0/CPU0     A9K-RSP440-TR(Active)     IOS XR RUN       PWR,NSHUT,MON
0/0/CPU0        A9K-4T16GE-TR             IOS XR RUN       PWR,NSHUT,MON

RP/0/RSP0/CPU0:LAB#show interfaces gigabitEthernet 0/0/0/2
Fri Oct 23 12:27:18.741 EDT
GigabitEthernet0/0/0/2 is up, line protocol is up
  Interface state transitions: 5
  Hardware is GigabitEthernet, address is d46d.5074.5ef6 (bia d46d.5074.5ef6)
  Internet address is 192.168.54.10/23
  MTU 1514 bytes, BW 1000000 Kbit (Max: 1000000 Kbit)
     reliability 255/255, txload 0/255, rxload 0/255
  Encapsulation ARPA,
  Full-duplex, 1000Mb/s, link type is force-up
  output flow control is off, input flow control is off
  Carrier delay (up) is 10 msec
  loopback not set,
  ARP type ARPA, ARP timeout 04:00:00
  Last input 00:00:00, output 00:00:00
  Last clearing of "show interface" counters never
  5 minute input rate 6000 bits/sec, 9 packets/sec
  5 minute output rate 0 bits/sec, 1 packets/sec
     2875724 packets input, 401523342 bytes, 722198 total input drops
     61731 drops for unrecognized upper-level protocol
     Received 1656322 broadcast packets, 1067316 multicast packets
              0 runts, 0 giants, 0 throttles, 0 parity
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     183061 packets output, 12151818 bytes, 0 total output drops
     Output 153253 broadcast packets, 0 multicast packets
     0 output errors, 0 underruns, 0 applique, 0 resets
     0 output buffer failures, 0 output buffers swapped out
     5 carrier transitions
 

RP/0/RSP0/CPU0:LAB#show interfaces gigabitEthernet 0/0/0/2
Fri Oct 23 12:31:21.667 EDT
GigabitEthernet0/0/0/2 is up, line protocol is up
  Interface state transitions: 5
  Hardware is GigabitEthernet, address is d46d.5074.5ef6 (bia d46d.5074.5ef6)
  Internet address is 192.168.54.10/23
  MTU 1514 bytes, BW 1000000 Kbit (Max: 1000000 Kbit)
     reliability 255/255, txload 0/255, rxload 0/255
  Encapsulation ARPA,
  Full-duplex, 1000Mb/s, link type is force-up
  output flow control is off, input flow control is off
  Carrier delay (up) is 10 msec
  loopback not set,
  ARP type ARPA, ARP timeout 04:00:00
  Last input 00:00:00, output 00:00:00
  Last clearing of "show interface" counters never
  5 minute input rate 6000 bits/sec, 9 packets/sec
  5 minute output rate 0 bits/sec, 1 packets/sec
     2877887 packets input, 401698878 bytes, 722745 total input drops
     61781 drops for unrecognized upper-level protocol
     Received 1657566 broadcast packets, 1068209 multicast packets
              0 runts, 0 giants, 0 throttles, 0 parity
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     183244 packets output, 12165994 bytes, 0 total output drops
     Output 153355 broadcast packets, 0 multicast packets
     0 output errors, 0 underruns, 0 applique, 0 resets
     0 output buffer failures, 0 output buffers swapped out
     5 carrier transitions
 

[Hamam Ismail]

Thanks Stephen,

Can you try loading the asr9k-mcast-px.pie-5.3.1? and then try the test.

[Stephen Craven]

We have installed the Multicast PIE, reloading the entire chassis afterwards, and the issue remains:

RP/0/RSP0/CPU0:SOC#show install sum
Mon Oct 26 15:32:17.934 EDT
Default Profile:
  SDRs:
    Owner
  Active Packages:
    disk0:asr9k-mini-px-5.3.1
    disk0:asr9k-mcast-px-5.3.1
    disk0:asr9k-mpls-px-5.3.1
    disk0:asr9k-k9sec-px-5.3.1

It's interesting to note that the interface claims that multicast is not supported (see highlights):

RP/0/RSP0/CPU0:SOC#show ptp interfaces gigabitEthernet 0/0/0/2
Mon Oct 26 15:33:11.672 EDT
GigabitEthernet0/0/0/2 is in Listen state
  PTP port number: 1
  IPv4 transport: IPv4 address 192.168.54.10
  Linestate: Up
  Mechanism: Two-step delay-request-response
  Sync rate: 64 per-second
  Announce rate: every 2 seconds, timeout 2 intervals
  Min Delay-Request rate: 64 per-second
  CoS: General 6, Event 6, DSCP: General 46, Event 46
  Platform capabilities:
    Supported:     One-step, Two-step, IPv4, Unicast, Master, Slave
    Not-supported: Ethernet, Multicast, IPv6, Source IP
    Max-Sync-rate: 128 per second
  Slave state only
  Master table:
  (K = Known, Q = Qualified, GM = Grandmaster,
   LA = PTSF LossAnnounce, LS = PTSF LossSync)
    IPv4-address 192.168.54.45: priority not set, LA
  0 Unicast peers

Is multicast PTP supported on the A9K-4T16GE?

Thank you,

Stephen

[Hamam Ismail · Accepted solution]

Hello Stephen,

Thanks for the output. The information you provided here shows us the reason why multicast will not work:

Platform capabilities:
    Supported:     One-step, Two-step, IPv4, Unicast, Master, Slave
    Not-supported: Ethernet, Multicast, IPv6, Source IP

Researching the internal threads, at this time the asr9k platform only supports unicast.

[dehagart]

Sorry about being a bit late, Stephen...

Plans to support multicast will probably be L2 (as specified by G.8275.1) rather than 1588v2 default profile with multicast (which seems to be what you are asking).

I'll see what I can do about fixing the doc.

[Nitin Pabbi]

Hi Stephen,

You correctly pointed out.

Multicast PTP is not supported on ASR9K as stated below in the output-

 RP/0/RSP0/CPU0:SOC#show ptp interfaces gigabitEthernet 0/0/0/2
Mon Oct 26 15:33:11.672 EDT
GigabitEthernet0/0/0/2 is in Listen state
  PTP port number: 1
  IPv4 transport: IPv4 address 192.168.54.10
  Linestate: Up
  Mechanism: Two-step delay-request-response
  Sync rate: 64 per-second
  Announce rate: every 2 seconds, timeout 2 intervals
  Min Delay-Request rate: 64 per-second
  CoS: General 6, Event 6, DSCP: General 46, Event 46
  Platform capabilities:
    Supported:     One-step, Two-step, IPv4, Unicast, Master, Slave
    Not-supported: Ethernet, Multicast, IPv6, Source IP
    Max-Sync-rate: 128 per second
  Slave state only
  Master table:
  (K = Known, Q = Qualified, GM = Grandmaster,
   LA = PTSF LossAnnounce, LS = PTSF LossSync)
    IPv4-address 192.168.54.45: priority not set, LA
  0 Unicast peers

On ASR9k we don't support multicast. This includes all LCs.

We will work with documentation team to update the ASR9k CCO docs.

Thanks

Nitin Pabbi

[Stephen Craven]

Thank you.

I would suggest that, in addition to correcting the documentation, you also remove the multicast command from the global PTP configuration. The router accepts this command globally without issue.

ptp
 profile tp64
  transport ipv4
  master ipv4 192.168.66.100
   multicast

 Are there any plans to add multicast support in the future?

[Nitin Pabbi]

Thanks for the suggestion Stephen.

Availability of this knob is because PTP code is same for all the platforms including ASR9k and data center.

Since DC devices support mcast, so knob is for their use.

but for ASR9k we have already initiated doc process so that users can get better idea about what is supported and what not.

in regard to mcast support in future, then I don't find it available in near future.

Thanks

Nitin Pabbi

[Tanasis Yankov]

Hi Nitin

But this documents suggest that there is such mode and it is supported

http://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k_r4-3/system_management/configuration/guide/b_sysman_cg43asr9k/b_sysman_cg43asr9k_chapter_01011.html

if multicast is not supported in "mixed" or multicast mode why its still in documentation ?

[Nitin Pabbi]

Hey Tanasis,

We have updated 5.3.x latest config guide.

http://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k_r5-3/sysman/configuration/guide/b-sysman-cg-53xasr9k/b-sysman-cg-53xasr9k_chapter_01100.html 

Unicast and Multicast Messages

PTP supports the following options for unicast and multicast:

• Unicast mode: In this mode, all PTP messages are sent as unicast messages. This is the default behavior.

• Mixed or Multicast mode (Not supported for ASR9000 series routers): In this mode, Announce and Sync messages are sent as multicast messages, while Signaling, Delay-Request and Delay-Response messages are only sent unicast

• IPv6 and Ethernet (not supported for ASR9000 series routers)

4.3.x config guide was not touched and seems creating confusion.

We will initiate the process for doc update for 4.3.x release as well.

Thanks

Nitin Pabbi