I had a problem trying to get Apache Geode (v1.0.0-incubating.M2) running on Linux.
The problem was: while I was trying to run gfsh start server --name=server1 example command from the documentation it gave me the following error:
Exception in thread "main" com.gemstone.gemfire.InternalGemFireError: Cannot resolve local host name to an IP address.
It turns out that you need to have your hostname (given by output of hostname command) be present in /etc/hosts file.
In my case, hostname gives an alias as an output (let's say my_alias), so I solved the problem by adding my_ip my_full_domain my_alias line to /etc/hosts.
Related
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.
I'm trying to follow the instructions here https://github.com/go-sql-driver/mysql#installation and http://go-database-sql.org/accessing.html to create a sql.db.
The first line of my code has this
db, err := sql.Open("mysql", "username#localhost/my_db")
When I ran the program on the terminal, I got this:
Default addr for network ''localhost'' unknown
Why is this? When I checked the user and host to mysql it states 'username' and 'localhost'. I followed the parameters like this:
[username[:password]#][protocol[(address)]]/dbname[?param1=value1&...¶mN=valueN]
You might want to specify the protocol (like 'tcp'), instead of localhost directly.
See those examples:
user:password#tcp(localhost:5555)/dbname
In your case:
username#tcp(localhost)/my_db
Note, if you use the default protocol (tcp) and host (localhost:3306), this could be rewritten as
user:password#/dbname
Lakshminarayanan Guptha adds in the comments:
In my case - user:password#tcp/dbname worked
I had the same problem and the most voted answer couldn't help me. What saved me was putting (host:port) inside quotation --> "(host:port)"
I had faced a similar issue as I was running Docker containers on my Linux VM. In my application (server.go) I changed the localhost value to use the IP of my virtual machine and then build and ran the container successfully.
mysql container (3307) <--> [(application mysql:<vm ip>:3307) container](expose 3000) <--> world
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 need to setup a hadoop/hdfs cluster with one namenode and two datanodes. I am aware of conf/slaves file which lists the machines datanodes are running. But how can I specify where hadoop/hdfs is locally installed on slave node? Also the user account to start hdfs there?
Edit: in log files, I find following error, when I tried to start-dfs.sh
ERROR org.apache.hadoop.hdfs.server.namenode.NameNode: java.lang.IllegalArgumentException: Does not contain a valid host:port authority: file:///
The user is expected to be the same as on the master node. The location of the actual data can be modified by changing the dfs.data.dir node inhadoop-site.xml.
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.