Setting Cassandra on server IP - configuration

I'm trying to switch Cassandra from localhost to server IP where cassandra has been installed.
In Cassandras config file:
cassandra.yaml
, I changed listen_address to my IP, also on seed and on rps_address.
Beyond on picture you can see that also I have changed name of Cluster to
First Cluster
But when i start CQLSH I got:
Where am I doing wrong?

If someone comes to this post and still don't know what the actually fu** is not working, here is the answer.
Listen address in cassandra always must stay on localhost but always. How to change the address than?
Go in
cassandra.yaml
,and change:
rpc_address = your_server_IP ( it's on localhost)
rpc_start = true ( he is on false)
When you are trying to access cassandra in shell than type it like this:
sh ~cassandra/bin/cqlsh your_server_IP_which_you_set_as_RPC_ADDR
Something like:
sh ~cassandra/bin/cqlsh 10.12.123.123

Related

How to connect to local MySQL Server 8.0 with DBIish in Perl6

I'm working on a Perl6 project, but having difficulty connecting to MySQL. Even when using the DBIish (or perl6.org tutorial) example code, the connection fails. Any suggestions or advice is appreciated! User credentials have been confirmed accurate too.
I'm running this on Windows 10 with MySQL Server 8.0 and standard Perl6 with Rakudo Star. I have tried modifying the connection string in numerous ways like :$password :password<> :password() etc. but can't get a connection established. Also should note that I have the ODBC, C, C++, and.Net connectors installed.
#!/usr/bin/perl6
use v6.c;
use lib 'lib';
use DBIish;
use Register::User;
# Windows support
%*ENV<DBIISH_MYSQL_LIB> = "C:/Program Files/MySQL/MySQL Server 8.0/liblibmysql.dll"
if $*DISTRO.is-win;
my $dbh = DBIish.connect('mysql', :host<localhost>, :port(3306), :database<dbNameHere>, :user<usernameHere>, :password<pwdIsHere>) or die "couldn't connect to database";
my $sth = $dbh.prepare(q:to/STATEMENT/);
SELECT *
FROM users
STATEMENT
$sth.execute();
my #rows = $sth.allrows();
for #rows { .print }
say #rows.elems;
$sth.finish;
$dbh.dispose;
This should be connecting to the DB. Then the app runs a query, followed by printing out each resulting row. What actually happens is the application hits the 'die' message every time.
This is more of a work around, but being unable to use use a DB is crippling. So even when trying to use the NativeLibs I couldn't get a connection via DBIish. Instead I have opted to using DB::MySQL which is proving to be quite helpful. With a few lines of code this module has your DB needs covered:
use DB::MySQL;
my $mysql = DB::MySQL.new(:database<databaseName>, :user<userName>, :password<passwordHere>);
my #users = $mysql.query('select * from users').arrays;
for #users { say "user #$_[0]: $_[1] $_[2]"; }
#Results would be:
#user #1: FirstName LastName
#user #2: FirstName LastName
#etc...
This will print out a line for each user formatted as shown above. It's not as familiar as DBIish, but this module gets the job done as needed. There's plenty more you can do with it to, so I highly recommend reading the docs.
According to this github DBIish issue 127
The environmental variable DBIISH_MYSQL_LIB was removed. I don't know if anyone brought it back.
However if you add the library's path, and the file is named mysql.dll, it will work. Not a good result for the scientific method.
So more testing is needed - and perhaps
C:\Program Files\MySQL\MySQL Server 8.0\lib>mklink mysql.dll .\libmysql.dll
Oviously you can create your own lib directory and add that to your path and then add this symlink to that directory.
Hope this helps. I've spent hours..
EDIT: Still spending time - accounting later.
Something very transitory is going on. I reset the machine (perhaps always do this from now on), and still got the missing mysql.dll errors. Tried going into the MySQL lib directory to execute raku from there.. worked. changed directories.. didn't work.
Launched administrator cmd - from home directory, tried the raku command. Worked. Ok - not good, but perhaps consistent. Launched non admin cmd, tried it from the MySQL lib directory, worked. And just for giggles, tried it outside of that directory.. worked.
Now I can't get it not to work. Will explore NativeLibs::Searcher as Valle Lukas suggested!
Maybe the example in the dbiish repository is not valid anymore.
The DBIISH_MYSQL_LIB Env seems to be replaced by NativeLibs::Searcher with commit 9bc4191
Looking at NativeLibs::Searcher may help to find the root cause of the problem.

go-ethereum - geth - puppeth - ethstat remote server : docker: command not found

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.

MySQL login-path issues with clustercheck script used in xinetd

default: on
# description: mysqlchk
service mysqlchk
{
# this is a config for xinetd, place it in /etc/xinetd.d/
disable = no
flags = REUSE
socket_type = stream
type = UNLISTED
port = 9200
wait = no
user = root
server = /usr/bin/mysqlclustercheck
log_on_failure += USERID
only_from = 0.0.0.0/0
#
# Passing arguments to clustercheck
# <user> <pass> <available_when_donor=0|1> <log_file> <available_when_readonly=0|1> <defaults_extra_file>"
# Recommended: server_args = user pass 1 /var/log/log-file 0 /etc/my.cnf.local"
# Compatibility: server_args = user pass 1 /var/log/log-file 1 /etc/my.cnf.local"
# 55-to-56 upgrade: server_args = user pass 1 /var/log/log-file 0 /etc/my.cnf.extra"
#
# recommended to put the IPs that need
# to connect exclusively (security purposes)
per_source = UNLIMITED
}
/etc/xinetd.d #
It is kind of strange that script works fine when run manually when it runs using /etc/xinetd.d/ , it is not working as expected.
In mysqlclustercheck script, instead of using --user= and passord= syntax, I am using --login-path= syntax
script runs fine when I run using command line but status for xinetd was showing signal 13. After debugging, I have found that even simple command like this is not working
mysql_config_editor print --all >>/tmp/test.txt
We don't see any output generated when it is run using xinetd ( mysqlclustercheck)
Have you tried the following instead of /usr/bin/mysqlclustercheck?
server = /usr/bin/clustercheck
I am wondering if you could test your binary location with the linux which command.
A long time ago since this question was asked, but it just came to my attention.
First of all as mentioned, Percona Cluster Control script is called clustercheck, so make sure you are using the correct name and correct path.
Secondly, since the server script runs fine from command line, it seems to me that the path of mysql client command is not known by the xinetd when it runs the Cluster Control script.
Since the mysqlclustercheck script as it is offered from Percona, it uses only the binary name mysql without specifying the absolute path I suggest you do the following:
Find where mysql client command is located on your system:
ccloud#gal1:~> sudo -i
gal1:~ # which mysql
/usr/local/mysql/bin/mysql
gal1:~ #
then edit script /usr/bin/mysqlclustercheck and in the following line:
MYSQL_CMDLINE="mysql --defaults-extra-file=$DEFAULTS_EXTRA_FILE -nNE --connect-timeout=$TIMEOUT \
place the exact path of mysql client command you found in the previous step.
I also see that you are not using MySQL connection credentials for connecting to MySQL server. mysqlclustercheck script as it is offered from Percona, it uses User/Password in order to connect to MySQL server.
So normally, you should execute the script in the command line like:
gal1:~ # /usr/sbin/clustercheck haproxy haproxyMySQLpass
HTTP/1.1 200 OK
Content-Type: text/plain
Where haproxy/haproxyMySQLpass is the MySQL connection user/pass for HAProxy monitoring user.
Additionally, you should specify them to your script's xinetd settings like:
server = /usr/bin/mysqlclustercheck
server_args = haproxy haproxyMySQLpass
Last but not least, the signal 13 you are getting is because you try to write something in a script run by xinetd. If for example in your mysqlclustercheck you try to add a statement like
echo "debug message"
you probably going to see the broken pipe signal (13 in POSIX).
Finally, I had issues with this script using SLES 12.3 and I finally manage to run it not as 'nobody' but as 'root'.
Hope it helps

error connecting to database with mysqldriver

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&...&paramN=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

UnknownHostException while formatting HDFS

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.