We have been attempting to utilize our K2000 v3.6.98680 appliance for systems deployment via multicasting unsuccessfully. After some initial research I found that our network configuration will need to support both PGM and Multicasting routing. We have PIM Sparse Dense Mode enabled for our network and numerous Cisco devices will not even support PGM. Would someone by chance be able to confirm my findings that we indeed cannot utilize the multicasting option due to the information above?

 

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The K2000 Uses Pragmatic General Multicast (PGM), here is an explanation of the protocol and some suggestions for configuring, troubleshooting and tweaking the deployment process.

 

·         Multicast Quick-Start Configuration Guide:

http://www.cisco.com/c/en/us/support/docs/ip/ip-multicast/9356-48.html

Pragmatic General Multicast (PGM) is a reliable multicast transport protocol for multicast applications that require reliable, ordered, duplicate-free multicast data delivery from multiple sources to multiple receivers. PGM guarantees that a receiver in a multicast group either receives all data packets from transmissions and retransmissions, or can detect unrecoverable data packet loss. PGM is intended as a solution for multicast applications with basic reliability requirements. There are no PGM global commands. PGM is configured per interface with the ip pgm command. You must enable Multicast routing on the router with PIM on the interface. PGM has two main parts: a host element (also referred to as the transport layer of the PGM protocol) and a network element (also referred to as the network layer of the PGM protocol). The transport layer of the PGM protocol has two main parts: a source part and a receiver part. The network layer of the PGM protocol defines how intermediate network devices (such as routers and switches) handle PGM transport data as the data flows through a network. PGM Router Assist is the Cisco implementation of the network layer of the PGM protocol. The transport layer defines how multicast applications send and receive reliable, ordered, duplicate-free multicast data from multiple sources to multiple receivers.

 

·         PGM Router Assist:

Recently proposed router-assisted schemes, such as PGM require certain modifications to routers in order to control and process the forwarding of feedbacks and retransmissions.

These schemes have become more popular as developments in ASIC (Application Specific Integrated Circuit) technology allow implementation of more complex functions in the router forwarding hardware.

They are also inspired by developments in active networking [24].

Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         Link to check that your Cisco switch is compatible with\supports PGM:

http://tools.cisco.com/ITDIT/CFN/jsp/by-feature-technology.jsp

 

·         CGMP and IGMP Snooping Catalyst Switches Support Matrix

This table provides information related to Cisco Group Management Protocol (CGMP) and Internet Group Management Protocol (IGMP) snooping feature support in Cisco Catalyst Switches.

http://www.cisco.com/c/en/us/support/docs/ip/ip-multicast/29480-167.html#topic1 

 Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         Enabling PGM Router Assist:

http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipmulti/command/imc-cr-book/imc_i3.html#wp8231331160]

http://www.cisco.com/c/en/us/td/docs/ios/12_2/ip/configuration/guide/fipr_c/1cfpgm.html#wp1001854

 

When enabling PGM Router Assist on your router, you must set up your router to forward PGM packets through a vif or out a physical interface installed in the router. Setting up your router to forward PGM packets through a vif enables the router to forward PGM packets through any router interface. The vif also serves as the interface to the multicast applications that reside at the PGM network layer. Setting up your router to forward PGM packets out a specific physical or logical interface type (for example, an Ethernet, serial, or loopback interface) configures the router to forward PGM packets out that interface only.

 

·         Enabling PGM Router Assist with a Virtual Host Interface:

To enable PGM Router Assist on a vif, use the following command in interface configuration mode:

Command;

Router(config-if)# ip pgm router

Purpose;

Enables the router to assist PGM on this interface.

Note You must configure a vif by using the interface vif number global configuration command on the router before enabling PGM Assist on the router; otherwise, PGM Assist will not be enabled on the router. See the "PGM Router Assist with a Virtual Interface Example" section later in this chapter for an example of enabling PGM Router Assist with a virtual interface.

Enabling PGM Router Assist with a Physical Interface:

To enable PGM Router Assist on the router and to configure the router to forward PGM packets through a physical interface, use the following commands in interface configuration mode:

Command;

Router(config-if)# ip pgm router

Purpose;

Enables the router to assist PGM on this interface.

Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         To Isolate any major issues, since the first step in resolving any issue is to find out what is the root cause, you can run an Integrity Test on the K2000:

K2000 Integrity Checkhttp://www.kace.com/support/resources/kb/solutiondetail?sol=SOL111771

 

·         If you have performance or reliability\stability issues, see:

K2000 Performancehttps://www.kace.com/support/resources/kb/solutiondetail?sol=SOL111769

i.e. hard setting the speed\duplex.

 

Ø  Enabling link aggregation:

By default, link aggregation is not enabled on the K2000 appliance.

The K2000 requires that your switch is capable of a LACP (802.3ad) connection.

Before you enable link aggregation, set your switch to actively negotiate LACP.

See your switch vendor's documentation for details. Passive negotiation mode does not work.

If your switch is set to operate in passive mode, the switch cannot negotiate the K2000 LACP connection.

For an example of a Cisco switch configuration running the IOS operating system set to active mode, view the online FreeBSD Handbook.

FreeBSD Handbook:

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-aggregation.html

Section 30.7.1. Configuration Examples

This section demonstrates how to configure a Cisco® switch and a FreeBSD system for LACP load balancing.

It then shows how to configure two Ethernet interfaces in failover mode as well as how to configure failover mode between an Ethernet and a wireless interface.

Subsection Example 30.1. LACP Aggregation with a Cisco® Switch

Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         2. Create an aggregate link

Enable link aggregation based on the destination IP address.

 

The K2000 appliance provides two ports. You must connect both ports to the network (LAN) for enabling link aggregation. When link aggregation is enabled, the second port cannot be explicitly used for offboard-storage configuration. Also, the link aggregation feature is not available when the offboard storage is explicitly configured with the K2000 server.

 

Procedure

Click Settings & Maintenance.

The Control Panel page appears.

 

Click Network Settings.

The Network Settings page appears.

 

Click Edit.

Select the Enable Link Aggregation check box.

Click Save.

Enter the Link Aggregation IP Address.

The K2000 reboots and the IP address changes to the link aggregation IP address you entered.

 

Note: The Subnet Mask changes to match the NIC.

 

·         IGMP:

IGMP messages are used primarily by multicast hosts to signal their interest in joining a specific

multicast group and to begin receiving group traffic.

The original IGMP Version 1 Host Membership model defined in RFC 1112 is extended to significantly

reduce leave latency and provide control over source multicast traffic by use of Internet Group

Management Protocol, Version 2.

IGMP Version 1

Provides for the basic Query-Response mechanism that allows the multicast router to determine

which multicast groups are active and other processes that enable hosts to join and leave a multicast

group. RFC 1112 defines Host Extensions for IP Multicasting.

IGMP Version 2

Extends IGMP allowing such features as the IGMP leave process, group-specific queries, and an

explicit maximum query response time. IGMP Version 2 also adds the capability for routers to elect

the IGMP querier without dependence on the multicast protocol to perform this task. RFC 2236

definesInternet Group Management Protocol, Version 2.

IGMP Version 3

Provides for “source filtering” which enables a multicast receiver host to signal to a router which

groups it wants to receive multicast traffic from, and from which sources this traffic is expected.

http://www.cisco.com/c/en/us/td/docs/ios/12_2s/feature/guide/fs_xtrc.html

 

Note: We recommend that you do not disable IGPM snooping on the device.

If you disable IGMP snooping, you might see reduced multicast performance because of excessive false flooding within the device.

Administrators must distinguish between IGMPv3 support at the router level and IGMPv3 snooping at the switch level. They are two different features.

Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         Cisco Group Management Protocol:

http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/10559-22.html#cgmp

CGMP was first implemented by Cisco to restrain multicast traffic in a L2 network. Because a switch is, by essence, not capable of looking at L3 packets, it cannot distinguish an IGMP packet. With CGMP, the router provides the interface between the hosts. The routers "talk" IGMP, and the switches "talk" CGMP.

Note: Please refer to your router’s specific documentation, regarding this process. If further assistance is required, please call\email\chat with the Original Equipment Manufacturer regarding assistance in configuring this, as Kace Support Personnel are unable to assist with the configuration.

 

·         The Transmission Rate may also be 'key' in obtaining reliable performance.

After trying the deployment at the maximun rate of 8000000 bytes per second.

Check the multicast log at -> Settings & Maintenance > Appliance Logs > K2000 Server Multicast Log.

 

Example Multicast Log;

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1341 -- }

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1340 -- avg_byte_per_sec : 119373.59 Bps

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1339 -- rate limited : 379

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1338 -- bytes remain : 0

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1337 -- bytes written : 8594898

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1336 -- write loop turns : 430

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1335 -- bon_time_remain : 0

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1334 -- bos_status_normal : 430

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1333 -- bos_would_block : 921

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1332 -- bos_rate_limited : 0

Mar 6 13:45:43 k2000 K2000 Multicast: (summary_counters ) line:1331 -- Final Counters = {

Mar 6 13:42:13 k2000 K2000 Multicast: (parseArgs ) line: 449 -- TimeToComplete : 2014-03-06 13:42:21 (00:00)

Mar 6 13:42:13 k2000 K2000 Multicast: (parseArgs ) line: 409 -- Setting max_rate to 1000000

Mar 6 13:42:13 k2000 K2000 Multicast: (main ) line: 969 -- spew built on Jan 7 2014 at 14:49:16

Mar 6 13:42:13 k2000 K2000 Multicast: (main ) line: 959 -- *** Starting K2000 Multicast Sender ***

Mar 6 00:00:00 k2000 newsyslog[24450]: logfile turned over

 

Search the log for 'avg_byte_per_sec'

This is the Maximum Sustainable Transfer Rate for your network [at least, for that session at that time, this may vary if you are able to schedule your deployments for off-peak network usage\hours and\or vary the # of clients joined to that multicast session].

 

To adjust thetransfer rate, you can goto -> Settings & Maintenance > Control Panel > Default Multicast Settings

 

Change the Transmission Rate to approximately what the average byte per seconds was listed at from the multicast log:

119373.59 Bps from our example, above.

 

v  References:

 

Cisco Multicast Quick-Start Configuration Guide:

http://www.cisco.com/c/en/us/support/docs/ip/ip-multicast/9356-48.html  

 

K2000 Integrity Check:

http://www.kace.com/support/resources/kb/solutiondetail?sol=SOL111771

 

K2000 Performance:

https://www.kace.com/support/resources/kb/solutiondetail?sol=SOL111769

 

FreeBSD Handbook:

 

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-aggregation.html

Answered 03/31/2014 by: gerald_mack
Senior Yellow Belt

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