Data node service is not started on one of my Hadoop cluster.
Data node logs has the following information...
Exception details on PC where datanode service is not started:
2015-08-12 15:51:09,331 INFO org.apache.hadoop.http.HttpServer2: HttpServer.start() threw a non Bind IOException
java.net.BindException: Port in use: localhost:0
at org.apache.hadoop.http.HttpServer2.openListeners(HttpServer2.java:919)
at org.apache.hadoop.http.HttpSe
...........................
On successful Data Node PCs the Log looks like this
2015-08-12 15:43:57,520 INFO org.apache.hadoop.http.HttpServer2: Jetty bound to port 34958
2015-08-12 15:43:57,520 INFO org.mortbay.log: jetty-6.1.26
2015-08-12 15:43:57,619 INFO org.mortbay.log: Started HttpServer2$SelectChannelConnectorWithSafeStartup#localhost:34958
I have tried fixing the ports in hdfs-site.xml as explained in the link
But this did not work. Please throw some light in fixing this issue.
Thanks
"localhost:0 "
please check your /etc/hosts ,most likely this file not set well
I have uncommented the following line in /etc/hosts and everything worked fine.
127.0.0.1 localhost
This problem is due to the port is already used, hence BindException Thrown. to fix this issue follow the below steps.
1.
run netstat -np command to know the port used with process id
2.
Kill process id for the port which is already bind.
Related
I am trying to setup a K3S cluster for learning purposes but I am having trouble connecting the master node with agents. I have looked several tutorials and discussions on this but I can't find a solution. I know I am probably missing something obvious (due to my lack of knowledge), but still help would be much appreciated.
I am using two AWS t2.micro instances with default configuration.
When ssh into the master and installed K3S using
curl -sfL https://get.k3s.io | sh -s - --no-deploy traefik --write-kubeconfig-mode 644 --node-name k3s-master-01
with kubectl get nodes, I am able to see the master
NAME STATUS ROLES AGE VERSION
k3s-master-01 Ready control-plane,master 13s v1.23.6+k3s1
So far it seems I am doing things right. From what I understand, I am supposed to configure the kubeconfig file. So, I accessed it by using
cat /etc/rancher/k3s/k3s.yaml
I copied the configuration file and the server info to match the private IP I took from AWS console, resulting in something like this
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: <lots_of_info>
server: https://<master_private_IP>:6443
name: default
contexts:
- context:
cluster: default
user: default
name: default
current-context: default
kind: Config
preferences: {}
users:
- name: default
user:
client-certificate-data: <my_certificate_data>
client-key-data: <my_key_data>
Then, I ran vi ~/.kube/config, and there I pasted the kubeconfig file
Finally, I grabbed the token with cat /var/lib/rancher/k3s/server/node-token, ssh into the other machine and then run the following
curl -sfL https://get.k3s.io | K3S_NODE_NAME=k3s-worker-01 K3S_URL=https://<master_private_IP>:6443 K3S_TOKEN=<master_token> sh -
The output is
[INFO] Finding release for channel stable
[INFO] Using v1.23.6+k3s1 as release
[INFO] Downloading hash https://github.com/k3s-io/k3s/releases/download/v1.23.6+k3s1/sha256sum-amd64.txt
[INFO] Downloading binary https://github.com/k3s-io/k3s/releases/download/v1.23.6+k3s1/k3s
[INFO] Verifying binary download
[INFO] Installing k3s to /usr/local/bin/k3s
[INFO] Skipping installation of SELinux RPM
[INFO] Creating /usr/local/bin/kubectl symlink to k3s
[INFO] Creating /usr/local/bin/crictl symlink to k3s
[INFO] Creating /usr/local/bin/ctr symlink to k3s
[INFO] Creating killall script /usr/local/bin/k3s-killall.sh
[INFO] Creating uninstall script /usr/local/bin/k3s-agent-uninstall.sh
[INFO] env: Creating environment file /etc/systemd/system/k3s-agent.service.env
[INFO] systemd: Creating service file /etc/systemd/system/k3s-agent.service
[INFO] systemd: Enabling k3s-agent unit
Created symlink /etc/systemd/system/multi-user.target.wants/k3s-agent.service → /etc/systemd/system/k3s-agent.service.
[INFO] systemd: Starting k3s-agent
By this output, it looks like I have created an agent. However, when I run kubectl get nodes in the master, I still get
NAME STATUS ROLES AGE VERSION
k3s-master-01 Ready control-plane,master 12m v1.23.6+k3s1
What is the thing I was supposed to do in order to get the agent connected to the master? I am guess I am probably missing something simple, but I just can't seem to find the solution. I've read all the documentation but it is still not clear to me where I am making the mistake. I've tried saving the private master IP and token into the agent as environmental variables with export K3S_TOKEN=master_token and K3S_URL=master_private_IP and then simply running curl -sfL https://get.k3s.io | sh - but I still can't see the worker nodes when running kubectl get nodes
Any help would be appreciated.
It might be your VM instance firewall that prevents appropriate connection from your master to the worker node (and vice versa). Official rancher documentation advise to disable firewall for (Red Hat/CentOS) Enterprise Linux:
It is recommended to turn off firewalld:
systemctl disable firewalld --now
If enabled, it is required to disable nm-cloud-setup and reboot the node:
systemctl disable nm-cloud-setup.service nm-cloud-setup.timer reboot
If you are using Ubuntu on your VM's, there is a different firewall tool (ufw).
In my case, allowing 6443 and 443(not sure if required) port TCP connections worked fine.
Allow port 6443 and TCP connection in all of your cluster machines:
sudo ufw allow 6443/tcp
Then apply k3s installation script in your worker node(s):
curl -sfL https://get.k3s.io | K3S_NODE_NAME=k3s-worker-1 K3S_URL=https://<k3s-master-1 IP>:6443 K3S_TOKEN=<k3s-master-1 TOKEN> sh -
This should work. If not, you can try adding additional allow rule for 443 tcp port as well.
A few options to check.
Check Journalctl for errors
journalctl -u k3s-agent.service -n 300 -xn
If using RaspberryPi for a worker node, make sure you have
cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1
as the very end of your /boot/cmdline.txt file. DO NOT PUT THIS VALUE ON A NEW LINE! Should just be appended to the end of the line.
If your master node(s) have self-signed certs, make sure you copy the master node's self signed cert to your worker node(s). In linux or raspberry pi copy cert to /usr/local/share/ca-certificates, then issue an
sudo update-ca-certificates
on the worker node
Don't forget to reboot the worker node after you make these changes!
Hope this helps someone!
I'm trying to setup a private ethereum test network using Puppeth (as Péter Szilágyi demoed in Ethereum devcon three 2017). I'm running it on a macbook pro (macOS Sierra).
When I try to setup the ethstat network component I get an "docker configured incorrectly: bash: docker: command not found" error. I have docker running and I can use it fine in the terminal e.g. docker ps.
Here are the steps I took:
What would you like to do? (default = stats)
1. Show network stats
2. Manage existing genesis
3. Track new remote server
4. Deploy network components
> 4
What would you like to deploy? (recommended order)
1. Ethstats - Network monitoring tool
2. Bootnode - Entry point of the network
3. Sealer - Full node minting new blocks
4. Wallet - Browser wallet for quick sends (todo)
5. Faucet - Crypto faucet to give away funds
6. Dashboard - Website listing above web-services
> 1
Which server do you want to interact with?
1. Connect another server
> 1
Please enter remote server's address:
> localhost
DEBUG[11-15|22:46:49] Attempting to establish SSH connection server=localhost
WARN [11-15|22:46:49] Bad SSH key, falling back to passwords path=/Users/xxx/.ssh/id_rsa err="ssh: cannot decode encrypted private keys"
The authenticity of host 'localhost:22 ([::1]:22)' can't be established.
SSH key fingerprint is xxx [MD5]
Are you sure you want to continue connecting (yes/no)? yes
What's the login password for xxx at localhost:22? (won't be echoed)
>
DEBUG[11-15|22:47:11] Verifying if docker is available server=localhost
ERROR[11-15|22:47:11] Server not ready for puppeth err="docker configured incorrectly: bash: docker: command not found\n"
Here are my questions:
Is there any documentation / tutorial describing how to setup this remote server properly. Or just on puppeth in general?
Can I not use localhost as "remote server address"
Any ideas on why the docker command is not found (it is installed and running and I can use it ok in the terminal).
Here is what I did.
For the docker you have to use the docker-compose binary. You can find it here.
Furthermore, you have to be sure that an ssh server is running on your localhost and that keys have been generated.
I didn't find any documentations for puppeth whatsoever.
I think I found the root cause to this problem. The SSH daemon is compiled with a default path. If you ssh to a machine with a specific command (other than a shell), you get that default path. This does not include /usr/local/bin for example, where docker lives in my case.
I found the solution here: https://serverfault.com/a/585075:
edit /etc/ssh/sshd_config and make sure it contains PermitUserEnvironment yes (you need to edit this with sudo)
create a file ~/.ssh/environment with the path that you want, in my case:
PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin
When you now run ssh localhost env you should see a PATH that matches whatever you put in ~/.ssh/environment.
I am trying to set up a BrowserQuest server that runs in openshift
I've been following this readme. Everything seems to go fine, I get to the end and run rhc app show bq and get the following output:
bq # http://bq-plantagenet.rhcloud.com/ (uuid: 55e4311189f5cf028d0000fc)
------------------------------------------------------------------------
Domain: plantagenet
Created: 8:18 AM
Gears: 1 (defaults to small)
Git URL: ssh://55e4311189f5cf028d0000fc#bq-plantagenet.rhcloud.com/~/git/bq.git/
SSH: 55e4311189f5cf028d0000fc#bq-plantagenet.rhcloud.com
Deployment: auto (on git push)
nodejs-0.10 (Node.js 0.10)
--------------------------
Gears: Located with smarterclayton-redis-2.6
smarterclayton-redis-2.6 (Redis)
--------------------------------
From: http://cartreflect-claytondev.rhcloud.com/reflect?github=smarterclayton/openshift-redis-cart
Website: https://github.com/smarterclayton/openshift-redis-cart
Gears: Located with nodejs-0.10
But when I try to access http://bq-plantagenet.rhcloud.com:8080/ in a browser, I get:
The connection has timed out
The server at bq-plantagenet.rhcloud.com is taking too long to respond
My questions are what is going wrong and how can I fix it? Many thanks for your consideration in reading through this and any suggestions you might have for resolving it
You need to access http://bq-plantagenet.rhcloud.com, leave off the port 8080, that is the port you listen on internally. You should also try checking your log files (https://developers.openshift.com/en/managing-log-files.html) to see what errors your application is producing.
I have a Cpanel Server.
It send emails correctly expect from 1 domain which hosted on the server , so when I try to send email from that domain using roundcube or Horde I got the errror
SMTP Error (451): Failed to add recipient "recipient#exmple.com" (Temporary local problem - please try later).
does anyone know why and how to fix this?
I found the porblem:
After reviewing the file /var/log/exim_mainlog using
tail -f /var/log/exim_mainlog
I noticed that the error was:
2013-05-29 20:04:28 SMTP connection from [127.0.0.1]:36797 (TCP/IP connection count = 1)
2013-05-29 20:04:28 lowest numbered MX record points to local host: domain.com (while verifying <user#domain.com> from host localhost.localdomain (domain.com) [127.0.0.1]:36797)
2013-05-29 20:04:28 H=localhost.localdomain (domain.com) [127.0.0.1]:36797 sender verify defer for <user#domain.com>: lowest numbered MX record points to local host
2013-05-29 20:04:28 H=localhost.localdomain (domain.com) [127.0.0.1]:36797 F=<user#domain.com> A=dovecot_login:narena temporarily rejected RCPT <recipient#exmple.com>: Could not complete sender verify
2013-05-29 20:04:28 SMTP connection from localhost.localdomain (domain.com) [127.0.0.1]:36797 closed by QUIT
so the main problem was:
lowest numbered MX record points to local host
after couple of search I found the soluation in http://forums.cpanel.net/f5/lowest-numbered-mx-record-points-local-host-73563.html
which was to:
login to WHM and go to Main >> DNS Functions >> Edit MX Entry for the domain
set MX priority to 0 for the related domain and save.
I had the same problem after running a script to fix directory permissions on a cPanel-powered server (CentOS 6.5). I checked the logfile (tail -f /var/log/exim_mainlog) and found this error:
require_files: error for /home/user_name/etc/domain.com: Permission denied
Just ran the following command and the issue was fixed:
chown -R user_name:mail /home/user_name/etc/
Hope this helps someone.
check the the file /var/log/exim_mainlog to see more information about the error
tail -f /var/log/exim_mainlog
while trying to send email
Check your MX Entry in Cpanel, if the existing domain priority is less than or equals to 0, set it to 1. Mine is fixed. Hope it will help you.
Wow, after about an hour of searching and meddling with different files, I'd caution any novice not to venture out editing anything before you have a backup or image if your server, as you can cause irrevocable damage to your server. So many people talking garbage about what you should do or test without any real solution.
Anyways, here's what worked for me:
Real problem: Exim was updated to latest version which has loads of bugs like this issue.
How I fixed my server:
Authenticate to Linux via SSH and run the command lines through which we download and install the old version of EXIM.
Command Line 1: wget https://ca1.dynanode.net/exim-4.93-3.el7.x86_64.rpm
Command Line 2: rpm -Uvh --oldpackage exim-4.93-3.el7.x86_64.rpm
Command Line 3: systemctl restart exim
Command Line 4: Systemctl restart clamd
Command Line 5: systemctl restart spamassassin
Optional: just type "Reboot" to restart your server
The command lines above does the following:
Downloads the old package (I'm sure you can google other sources with this file)
Install the old package without prompt
Restart the Exim service
Restart the Clamd Service (AV)
Restart the spamassassin service (Spam Filter)
Restart outlook or whatever you use for mail client and send an email. Mine works, hope yours do too.
I have installed CDH4 on CentOS 6.3 64-bit in Pseudo Distributed mode using the following instructions. Everything is set to localhost in the Hadoop configuration files. But, still when I format the name node the below exception appears. When I add an 192.168.1.101 CentOSHost entry to the /etc/hosts file the exception goes away and I am able to run format/start HDFS and run MR jobs.
I want to run MR jobs even when I am not connected to the network without adding an entry to the /etc/hosts file. How to get this done?
12/08/27 22:17:15 WARN net.DNS: Unable to determine address of the host-falling back to "localhost" address
java.net.UnknownHostException: CentOSHost: CentOSHost
at java.net.InetAddress.getLocalHost(InetAddress.java:1360)
at org.apache.hadoop.net.DNS.resolveLocalHostIPAddress(DNS.java:283)
at org.apache.hadoop.net.DNS.(DNS.java:59)
at org.apache.hadoop.hdfs.server.namenode.NNStorage.newBlockPoolID(NNStorage.java:1017)
at org.apache.hadoop.hdfs.server.namenode.NNStorage.newNamespaceInfo(NNStorage.java:565)
at org.apache.hadoop.hdfs.server.namenode.FSImage.format(FSImage.java:145)
at org.apache.hadoop.hdfs.server.namenode.NameNode.format(NameNode.java:724)
at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1095)
at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1193)
It looks like some where the configuration is returning/ using the hostname as CentOSHost.
What does hostname --fqdn returns to you?
For Hadoop, it is important that name look-up and reverse look-up work successfully. You should be able to resolve the ip-address and resolve hostname from the ip-address (Reverse resolution). This can be tested using the above command.
The entry to /etc/hosts is required for the reverse resolution to work. Unless the entry and the configuration are pointing to localhost. Even in that case the hostname --fqdn should return as localhost.