Re: [j-nsp] R: RE : multicast issue
- Original Message - From: david@orange.com To: dim0sal dim0...@hotmail.com Cc: juniper-nsp@puck.nether.net Sent: Tuesday, July 16, 2013 8:49 PM Subject: Re: [j-nsp] R: RE : multicast issue If you can't start/stop manually mcast streams you will never have stable counters and can't detect packet loss. This is not exactly true. What You can do with constantly running streams is to have a FW filter with specific term matching on chosen stream IP headers+count action, on both headend (HE) and tailend (TE). Then activate/deactivate this term as required. You have to have both HE and TE synced via common NTP source and perform commits at precise times (commit at if You do it manually). Assuming headend and tailed are same router models and You have no network loss, You MAY get some minuscule counter difference between HE/TE because time spent by Routing Engine doing commit slightly varies. What would be more important is to monitor whether this difference changes with time which indicates packet loss. HTH Thanks Alex ___ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp
Re: [j-nsp] R: RE : multicast issue
If you can't start/stop manually mcast streams you will never have stable counters and can't detect packet loss. What you could do is to monitor customer mcast rate per (S,G) with the same snmp counters but it requieres you have constant bit rate for your (S,G). We have also this kind of script in perl which detects rate falling of (S,G) and triggers alarms when a given threshold is reach. It works very well for mcast TV channels (But you don't have the number of packet loss) Best regards Envoyé de mon iPad Le 16 juil. 2013 à 21:14, dim0sal dim0...@hotmail.commailto:dim0...@hotmail.com a écrit : Hi roy Good suggestions. Thanks. Anyway we re not able to start monitoring mcast flows since we get by external sources. We could perform the snmp get on the devices but since is not done in the same moment and routers are placed in different locations I expect the forwarded pkts will be different and the delta as well... What do you think? Inviato da Samsung Mobile Messaggio originale Da: david@orange.commailto:david@orange.com Data: A: R S dim0...@hotmail.commailto:dim0...@hotmail.com,John Neiberger jneiber...@gmail.commailto:jneiber...@gmail.com Cc: juniper-nsp@puck.nether.netmailto:juniper-nsp@puck.nether.net Oggetto: RE : [j-nsp] multicast issue Hello, We use mcast streams dedicated for multicast monitoring which are flooded to the entire network (some specific (S;G) ). we are able to start / stop automatically these streams. We developed a perl script which does : While(1) ( - Stop multicast monitoring streams - Get via SNMP GET the forwarded packets for each (S;G) on every routers of the network (Multicast MIB gives per S;G forwarded packets - Restart the streams - Wait 1 hour - Stop again streams - Get again via SNMP GET the per (S;G) forwarded packets per routers - compute the delta forwarded packet per node - detect packet loss and alert via snmp trap / mail which nodes loss some packets - Start the stream for 1 hour ) Best reagrd De : juniper-nsp [juniper-nsp-boun...@puck.nether.netmailto:juniper-nsp-boun...@puck.nether.net] de la part de R S [dim0...@hotmail.commailto:dim0...@hotmail.com] Date d'envoi : mardi 16 juillet 2013 18:55 À : John Neiberger Cc : juniper-nsp@puck.nether.netmailto:juniper-nsp@puck.nether.net Objet : Re: [j-nsp] multicast issue Hi John it's not a problem of how/why the packet lose, my concern is how can we monitor the multicast traffic hence our NOC is able to see the problem before the customer... It's multicast coming from financial markets. Tks From: jneiber...@gmail.commailto:jneiber...@gmail.com Date: Tue, 16 Jul 2013 10:42:18 -0600 Subject: Re: [j-nsp] multicast issue To: dim0...@hotmail.commailto:dim0...@hotmail.com CC: juniper-nsp@puck.nether.netmailto:juniper-nsp@puck.nether.net What sort of multicast traffic is it? Is it a constant stream like voice or video or is it an intermittent feed like some sort of multicast messaging? If this is very low-rate traffic and intermittent, Juniper routers often drop the first packet because the multicast route has timed out of the forwarding table and it gets punted to the RE. If that is what is happening, there is a workaround. If you're losing traffic mid-stream, that's a different issue entirely. John On Tue, Jul 16, 2013 at 10:14 AM, R S dim0...@hotmail.commailto:dim0...@hotmail.com wrote: Hi all Just a brainstorming and your possible help. I manage a network where multicast is the most important traffic and sometimes I get issue by customer where they state that some packets are lost… Does anybody have an idea or can help me in understanding a possible solution in monitoring traffic in real time manner, maybe with the use of some software or appliance or whatelse. In my idea I could monitor traffic on the source and on the destination, then with a sort of parsing understand if it’s my network loosing the packets or not… Any idea ? suggestion ? tks ___ juniper-nsp mailing list juniper-nsp@puck.nether.netmailto:juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp ___ juniper-nsp mailing list juniper-nsp@puck.nether.netmailto:juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp _ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, Orange decline toute responsabilite si ce message a ete altere,
[j-nsp] R: RE : multicast issue
Hi roy Good suggestions. Thanks. Anyway we re not able to start monitoring mcast flows since we get by external sources. We could perform the snmp get on the devices but since is not done in the same moment and routers are placed in different locations I expect the forwarded pkts will be different and the delta as well... What do you think? Inviato da Samsung Mobile Messaggio originale Da: david@orange.com Data: A: R S dim0...@hotmail.com,John Neiberger jneiber...@gmail.com Cc: juniper-nsp@puck.nether.net Oggetto: RE : [j-nsp] multicast issue Hello, We use mcast streams dedicated for multicast monitoring which are flooded to the entire network (some specific (S;G) ). we are able to start / stop automatically these streams. We developed a perl script which does : While(1) ( - Stop multicast monitoring streams - Get via SNMP GET the forwarded packets for each (S;G) on every routers of the network (Multicast MIB gives per S;G forwarded packets - Restart the streams - Wait 1 hour - Stop again streams - Get again via SNMP GET the per (S;G) forwarded packets per routers - compute the delta forwarded packet per node - detect packet loss and alert via snmp trap / mail which nodes loss some packets - Start the stream for 1 hour ) Best reagrd De : juniper-nsp [juniper-nsp-boun...@puck.nether.net] de la part de R S [dim0...@hotmail.com] Date d'envoi : mardi 16 juillet 2013 18:55 À : John Neiberger Cc : juniper-nsp@puck.nether.net Objet : Re: [j-nsp] multicast issue Hi John it's not a problem of how/why the packet lose, my concern is how can we monitor the multicast traffic hence our NOC is able to see the problem before the customer... It's multicast coming from financial markets. Tks From: jneiber...@gmail.com Date: Tue, 16 Jul 2013 10:42:18 -0600 Subject: Re: [j-nsp] multicast issue To: dim0...@hotmail.com CC: juniper-nsp@puck.nether.net What sort of multicast traffic is it? Is it a constant stream like voice or video or is it an intermittent feed like some sort of multicast messaging? If this is very low-rate traffic and intermittent, Juniper routers often drop the first packet because the multicast route has timed out of the forwarding table and it gets punted to the RE. If that is what is happening, there is a workaround. If you're losing traffic mid-stream, that's a different issue entirely. John On Tue, Jul 16, 2013 at 10:14 AM, R S dim0...@hotmail.com wrote: Hi all Just a brainstorming and your possible help. I manage a network where multicast is the most important traffic and sometimes I get issue by customer where they state that some packets are lost… Does anybody have an idea or can help me in understanding a possible solution in monitoring traffic in real time manner, maybe with the use of some software or appliance or whatelse. In my idea I could monitor traffic on the source and on the destination, then with a sort of parsing understand if it’s my network loosing the packets or not… Any idea ? suggestion ? tks ___ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp ___ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp _ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. This message and its attachments may contain confidential or privileged information that may be protected by law; they should not be distributed, used or copied without authorisation. If you have received this email in error, please notify the sender and delete this message and its attachments. As emails may be altered, Orange is not liable for messages that have been modified, changed or falsified. Thank you. ___ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp
