On Nov 15, 2005, at 7:11 PM, Herbert Poetzl wrote:
On Mon, Nov 14, 2005 at 03:09:32AM -0600, Drew Lippolt wrote:
QUESTION: what is the current story with multicast support for both
sending and receiving multicast traffic?
BACKGROUND:
trying to get tomcat clustering working in vserver.
http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html
DETAILS:
[EMAIL PROTECTED] opt]# cat /proc/version
Linux version 2.4.30-vs1.2.10 ([EMAIL PROTECTED]) (gcc version
3.2.3 20030502 (Red Hat Linux 3.2.3-52)) #1 Wed Aug 10 01:27:44
CDT 2005
[EMAIL PROTECTED] opt]# grep MULTICAST /boot/config-2.4.30-vs1.2.10
CONFIG_IP_MULTICAST=y
tomcat 5.5.12
i'm running debian sarge vservers on redhat enterprise linux 3.0
boxes at rackspace, using a stock kernel.org kernel with required
tweaks for my hardware this is a production environment which has
been supporting many apps beautifully for 3 months.
the basic idea is that i have multiple app layer boxes, which i want
to distribute tomcat clusters. single instance of tomcat, running in
a single vserver, per real host, per application. so if i have 3
apps, on 3 real servers, i'd have 9 total vservers across 3
clusters. i'm not even getting that far. my test setup is 2 real
hosts, each with one vserver with an 'out of the box' tomcat cluster
config. the tomcat instances aren't finding each other.
the stacktraces i'm getting on tomcat --shutdown-- are as follows,
which doesn't look all that interesting, its in code looking for
incoming connections on a tcp port, which never arrive, since the
mcast conversation never happens (ReplicationListener.java:130):
SEVERE: Unable to process request in ReplicationListener
java.nio.channels.ClosedSelectorException
at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:
55)
at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:70)
at org.apache.catalina.cluster.tcp.ReplicationListener.listen
(ReplicationListener.java:130)
at org.apache.catalina.cluster.tcp.ClusterReceiverBase.run
(ClusterReceiverBase.java:394)
at java.lang.Thread.run(Thread.java:534)
THINGS I"VE TRIED:
* add multicast ip to IPROOT. this just causes barf messages at
vserver startup
Starting the virtual server v208
Server v208 is not running
SIOCSIFADDR: Invalid argument
SIOCSIFFLAGS: Cannot assign requested address
SIOCSIFNETMASK: Cannot assign requested address
SIOCGIFADDR: Cannot assign requested address
SIOCSIFBROADCAST: Cannot assign requested address
SIOCSIFBRDADDR: Cannot assign requested address
SIOCSIFFLAGS: Cannot assign requested address
ipv4root is now 192.168.1.208 228.0.0.4
how did you add it?
tried a few different ways.
IPROOT="192.168.1.237 228.0.0.4"
IPROOT="192.168.1.237 228.0.0.4/224.0.0.0"
* enabled NET_ADMIN and NET_BROADCAST. this offers no change
well, NET_ADMIN is what you probably need for
multicasting, NET_BROADCAST should suffice for
multicast reception ...
the following are true, with NET_ADMIN, NET_BROADCAST, NET_RAW,
SYS_ADMIN all set
* clustering tool's test case suggests i'm SENDING multicast
traffic, but not RECEIVING
* tcpdump suggests i'm SENDING but not RECIEVING
* i can ping the multicast address from the shell while the app
server is running, but not when its not running
* adding routes doesn't seem to effect it at all
if you are interested in 'improving' multicast
capabilities in a safe way, and willing to do
some testing, please contact me on the IRC
channel ...
i'm down for whatever. i have a good testbed. i just missed you on
irc tonight. will try againtomorrow.
best,
Herbert
PS: will require switching to 2.6 kernel and
recent devel version (2.1.x)
i'm planning on moving to 2.6 anyway. we can chat about the 2.1.x
stuff.
<snip>
_______________________________________________
Vserver mailing list
Vserver@list.linux-vserver.org
http://list.linux-vserver.org/mailman/listinfo/vserver
