elasticsearch throws exceptions when logstash is running in standalone mode

Hello,

I have recently started exploring logstash after i heard it from my peers who attended puppetconf 2012

We have deployed logstash 1.1.9 in standalone mode with embedded elasticsearch on a EC2 instance.
We have also installed kibana as a frontend for logstash.
Since, we are using the embedded version of elasticsearch, i assume it doesn't have any compatibility issues with logstash version.

{:message=>"Failed to index an event, will retry", :exception=>org.elasticsearch.discovery.MasterNotDiscoveredException: waited for [1m], :event=>{"@source"=>"file://ip-10-xx-xx-xx.ec2.internal/var/log/messages", "@tags"=>[], "@fields"=>{}, "@timestamp"=>"2013-03-01T09:08:39.998Z", "@source_host"=>"ip-10-157-xx-xx.ec2.internal", "@source_path"=>"/var/log/messages", "@message"=>"Mar 1 00:14:52 ip-10-122-70-221@type"=>"linuxsyslog"}, :level=>:warn}

I am also seeing following exception

{:message=>"Failed to index an event, will retry", :exception=>org.elasticsearch.transport.RemoteTransportException: [Imperial Hydra][inet/10.157.38.34:9300][index], :event=>{"@source"=>"file://ip-10-xx-xx-xx.ec2.internal/var/log/", "@tags"=>[], "@fields"=>{}, "@timestamp"=>"2013-02-27T13:49:13.515Z", "@source_host"=>"ip-10-xx-xx-xx.ec2.internal", "@source_path"=>"/var/log/",

{:message=>"Failed to index an event, will retry", :exception=>org.elasticsearch.transport.RemoteTransportException: [Ariann]
{:message=>"Failed to index an event, will retry", :exception=>org.elasticsearch.transport.RemoteTransportException: [Gorgon]
{:message=>"Failed to index an event, will retry", :exception=>org.elasticsearch.transport.RemoteTransportException: [Forgotten One]

following processes are running on the host

root 22155 1 1 00:11 pts/0 00:01:52 /usr/bin/java -jar /opt/logstash/bin/logstash.jar agent --config /opt/logstash/conf/logstash.conf --log /opt/logstash/log/logstash.log --grok-patterns-path /opt/logstash/patterns
root 22039 1 0 00:08 ? 00:00:01 ruby kibana.rb

root 28932 13009 0 02:05 pts/0 00:00:00 grep -i java
tcp 0 0 0.0.0.0:9200 0.0.0.0:* LISTEN 22155/java
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 22039/ruby
tcp 0 0 0.0.0.0:9300 0.0.0.0:* LISTEN 22155/java
tcp 0 0 0.0.0.0:9301 0.0.0.0:* LISTEN 22155/java

logstash.conf
================

input {
file {
type => "linuxsyslog"

1. Wildcards work, here
   path => [ "/var/log/messages*" ]
   sincedb_path => "/opt/logstash"
   }

file {
type => "merrors"
path => [ "/var/log/m.errors*" ]
sincedb_path => "/opt/logstash"
}

file {
type => "mall"
path => [ "/var/log/m*" ]
exclude => [ "/var/log/m.errors*" ]
sincedb_path => "/opt/logstash"
}
}

filter {

date {
type => "syslog"
syslog_timestamp => [ "MMM d HH:mm:ss", "MMM dd HH:mm:ss" ]
}
}

output {
elasticsearch {
embedded => true
host => "10.157.3x.3x"
}
}

If i restart logstash and try to use the search engine, it works and gives output for a while, before it starts complaining about the above errors.

Please suggest on how to fix these errors.

Thanks