# ES Multicast Not Working, Multicasting enabled and working otherwise **URL:** \ **Category:** Elasticsearch\ **Created:** [August 1, 2015, 7:59pm UTC](https://discuss.elastic.co/t/es-multicast-not-working-multicasting-enabled-and-working-otherwise/26684 "2015-08-01T19:59:02Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![ryan](https://avatars.discourse-cdn.com/v4/letter/r/a8b319/32.png) [@ryan](https://discuss.elastic.co/u/ryan)\ **Post date:** [August 1, 2015, 7:59pm UTC](https://discuss.elastic.co/t/es-multicast-not-working-multicasting-enabled-and-working-otherwise/26684/1 "2015-08-01T19:59:02Z")
Hello, Are there any particular steps to debugging zen discovery using multicasting? I'm able to send multicast traffic between two nodes following these steps: > **[Generating Multicast Traffic](https://taosecurity.blogspot.com/2006/09/generating-multicast-traffic.html)** > > If you're a protocol junkie like me, you probably enjoy investigating a variety of network traffic types. I don't encounter multicast traff... Here's the output to confirm multicasting is enabled at the router level and functional on the network: ## iperf -s -u -B 224.0.55.55 -i 1 ## Server listening on UDP port 5001 Binding to local address 224.0.55.55 Joining multicast group 224.0.55.55 Receiving 1470 byte datagrams UDP buffer size: 8.00 MByte (default) [3] local 224.0.55.55 port 5001 connected with 209.41.67.68 port 56666 [ID] Interval Transfer Bandwidth Jitter Lost/Total Datagrams [3] 0.0- 1.0 sec 128 KBytes 1.05 Mbits/sec 0.010 ms 0/ 89 (0%) [3] 1.0- 2.0 sec 128 KBytes 1.05 Mbits/sec 0.018 ms 0/ 89 (0%) [3] 2.0- 3.0 sec 128 KBytes 1.05 Mbits/sec 0.024 ms 0/ 89 (0%) [3] 0.0- 3.0 sec 386 KBytes 1.05 Mbits/sec 0.023 ms 0/ 269 (0%) eth0 appears to bind to the 224.2.2.4 IP: netstat -g IPv6/IPv4 Group Memberships Interface RefCnt Group * * * lo 1 [all-systems.mcast.net](http://all-systems.mcast.net) eth0 1 224.2.2.4 eth0 1 [all-systems.mcast.net](http://all-systems.mcast.net) lo 1 ip6-allnodes lo 1 ff01::1 eth0 1 ff02::1:ff84:7902 eth0 1 ip6-allnodes eth0 1 ff01::1 eth1 1 ip6-allnodes eth1 1 ff01::1 Any suggestions on how to debug why nodes are unable to discover eachother using multicast is greatly appreciated. Thanks! Ryan ---
**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\ **Post date:** [August 2, 2015, 2:47am UTC](https://discuss.elastic.co/t/es-multicast-not-working-multicasting-enabled-and-working-otherwise/26684/2 "2015-08-02T02:47:15Z")
What do the logs say? ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 5, 2017, 11:57pm UTC](https://discuss.elastic.co/t/es-multicast-not-working-multicasting-enabled-and-working-otherwise/26684/3 "2017-07-05T23:57:52Z")