Good call! netstat -anl gives me:
tcp 0 0 ::ffff:127.0.0.1:8020
:::* LISTEN
Now it just looks like nothing is running on 8021. And now I'm really
confused about why I get no communication over 8020 from the datanode.
Just to reiterate, this definitely is not the firewall, running iptables
-nvL gives:
...
0 0 ACCEPT tcp -- * * 0.0.0.0/0
0.0.0.0/0 state NEW tcp dpt:50070
1 64 ACCEPT tcp -- * * 0.0.0.0/0
0.0.0.0/0 state NEW tcp dpt:50030
0 0 ACCEPT tcp -- * * 0.0.0.0/0
0.0.0.0/0 state NEW tcp dpt:8021
1 64 ACCEPT tcp -- * * 0.0.0.0/0
0.0.0.0/0 state NEW tcp dpt:8020
...
On 1/9/12 5:08 PM, alo.alt wrote:
What happen when you try a "telnet localhost 8020"?
netstat -anl would also useful.
best,
Alex
--
Alexander Lorenz
http://mapredit.blogspot.com
On Jan 9, 2012, at 2:02 PM, Eli Finkelshteyn wrote:
A bit more info:
When I start up only the namenode by itself, I'm not seeing any errors, but
what I am seeing that's really odd is:
2012-01-09 16:48:45,530 INFO org.apache.hadoop.ipc.Server: Starting
Socket Reader #1 for port 8020
2012-01-09 16:48:45,531 INFO
org.apache.hadoop.ipc.metrics.RpcMetrics: Initializing RPC Metrics
with hostName=NameNode, port=8020
2012-01-09 16:48:45,532 INFO
org.apache.hadoop.ipc.metrics.RpcDetailedMetrics: Initializing RPC
Metrics with hostName=NameNode, port=8020
2012-01-09 16:48:45,541 INFO
org.apache.hadoop.hdfs.server.namenode.NameNode: Namenode up at:
localhost.localdomain/127.0.0.1:8020
That's despite the fact that doing netstat -a | grep 8020 still returns
nothing. To me, that makes absolutely no sense. I feel like I should be
getting an error telling me Namenode did not in fact go up on 8020, but I'm not
getting that at all.
Eli
On 1/9/12 3:22 PM, Idris Ali wrote:
Hi,
Looks like problem in starting DFS and MR, can you run 'jps' and see if NN,
DN, SNN, JT and TT are running,
also make sure for pseudo-distributed mode, the following entries are
present:
1. In core-site.xml
<property>
<name>fs.default.name</name>
<value>hdfs://localhost:8020</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value><SOME TMP dir with Read/Write acces not system temp></value>
</property>
<property>
2. In hdfs-site.xml
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.permissions</name>
<value>false</value>
</property>
<property>
<!-- specify this so that running 'hadoop namenode -format' formats
the right dir -->
<name>dfs.name.dir</name>
<value>Local dir with Read/Write access</value>
</property>
3. In mapred-stie.xml
<property>
<name>mapred.job.tracker</name>
<value>localhost:8021</value>
</property>
Thanks,
-Idris
On Tue, Jan 10, 2012 at 1:07 AM, Eli Finkelshteyn<[email protected]>wrote:
Positive. Like I said before, netstat -a | grep 8020 gives me nothing.
Even if the firewall was the problem, that should still give me output that
the port is listening, but I'd just be unable to hit it from an outside box
(I tested this by blocking port 50070, at which point it still showed up in
netstat -a, but was inaccessible through http from a remote machine). This
problem is something else.
On 1/9/12 2:31 PM, zGreenfelder wrote:
On Mon, Jan 9, 2012 at 1:58 PM, Eli
Finkelshteyn<iefinkel@gmail.**com<[email protected]>>
wrote:
More info:
In the DataNode log, I'm also seeing:
2012-01-09 13:06:27,751 INFO org.apache.hadoop.ipc.Client: Retrying
connect
to server: localhost/127.0.0.1:8020. Already tried 9 time(s).
Why would things just not load on port 8020? I feel like all the errors
I'm
seeing are caused by this, but I can't see any errors about why this
occurred in the first place.
are you sure there isn't a firewall in place blocking port 8020?
e.g. iptables on the local machines? if you do
telnet localhost 8020
do you make a connection? if you use lsof and/or netstat can you see
the port open?
if you have root access you can try turning off the firewall with
iptables -F to see if things work without firewall rules.
