Which YugabyteDB node am I connected to? - high-availability

When using hosts list or JDBC smart driver, we can be connected to any database node in the cluster, or part of it. How can I know know which one I am currently connected to? With its availability zone, region, and cloud provider information?

YugabyteDB yb_servers() exposes all nodes, with their placement, and PostgreSQL inet_server_port() exposes the server endpoint you are connected to, so joining both:
with yb_servers as (
select host,port,cloud,region,zone from yb_servers()
), my_connection as (
select host(inet_server_addr()) host, inet_server_port() port
,'<<- you are here' as inet_server)
select * from yb_servers natural left join my_connection;
gives the following:
yugabyte=# with yb_servers as (
yugabyte(# select host,port,cloud,region,zone from yb_servers()
yugabyte(# ), my_connection as (
yugabyte(# select host(inet_server_addr()) host, inet_server_port() port,'<<- you are here' as inet_server)
yugabyte-# select * from yb_servers natural left join my_connection;
host | port | cloud | region | zone | inet_server
----------------+------+-------+------------+-------------+------------------
172.129.25.209 | 5433 | aws | eu-west-1 | eu-west-1a | <<- you are here
172.125.42.26 | 5433 | aws | ap-south-1 | ap-south-1b |
172.121.27.101 | 5433 | aws | us-east-2 | us-east-2a |
(3 rows)

Related

(FlywaySqlException in Spring) Password authentication failed for user

I try to connect my Spring-Boot-Application with new PostgreSQL USER (named : localX_deletion), but when i run it, that return me FlywaySqlException :
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'flywayInitializer' defined in class path resource [org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration$FlywayConfiguration.class]: Invocation of init method failed; nested exception is org.flywaydb.core.internal.exception.FlywaySqlException:
Unable to obtain connection from database: FATAL: password authentication failed for user "localX_deletion"
SQL State : 28P01 Error Code : 0 Message : FATAL : password authentication failed for user "localX_deletion"
I dont understand because i can connect with this user in command-line : psql -U localX_deletion -h localhost and when i specify in spring.datasource another account the application run as excepted.
How i create Database/Role:
CREATE USER localx_deletion;
CREATE DATABASE localx_deletion OWNER localx_deletion;
ALTER USER localx_deletion WITH ENCRYPTED PASSWORD 'localx_deletion';
ALTER DATABASE localx_deletion OWNER TO localx_deletion;
GRANT ALL PRIVILEGES ON DATABASE localx_deletion TO localx_deletion;
What i have already tried to fix it:
For each tasks bellow i have restart postgresql service.
Update password/name role.
Delete all and re-create all.
Setting in pg_hba.conf local and host as trust (that works but i dont like update this file, because the old config work fine with the others roles/databases).
Purge, remove and reinstall Postgresql
Someone have an idea for fix it please ?
\du - List of roles
Role name | Attributes | Member of
------------------------+------------------------------------------------------------+-----------
localx | Create DB | {}
localx_standalone | Create DB | {}
localx_standalone_test | Create DB | {}
localx_deletion | Create DB | {}
localx_test | Create DB | {}
postgr
\l - List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
------------------------+------------------------+----------+-------------+-------------+-----------------------------------
localx | postgres | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 | =Tc/postgres +
| | | | | postgres=CTc/postgres +
| | | | | localx=CTc/postgres
localx_standalone | localx_standalone | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 |
localx_standalone_test | localx_standalone_test | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 |
localx_deletion | localx_deletion | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 | =Tc/localx_deletion +
| | | | | localx_deletion=CTc/localx_deletion
localx_test | localx_test | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 |
postgres | postgres | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 |
template0 | postgres | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 | =c/postgres +
| | | | | postgres=CTc/postgres
template1 | postgres | UTF8 | fr_FR.UTF-8 | fr_FR.UTF-8 | =c/postgres +
| | | | | postgres=CTc/postgres
pg_hba.conf
# Database administrative login by Unix domain socket
local all postgres peer
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
# Allow replication connections from localhost, by a user with the
# replication privilege.
local replication all peer
host replication all 127.0.0.1/32 md5
host replication all ::1/128 md5
Operating System : Ubuntu 20.04.1 LTS (Focal Fossa), Postgresql : 12

How do you measure query performance in Cassandra?

I am still new in learning Cassandra, and I am doing some measurements, regarding memory and processor resources for each of my query. Does Cassandra has her own way to show performance of query or should I use some third party tool?
You can use the tracing switched on to see the internal steps.
TRACING ON
For the query below
INSERT INTO cycling.cyclist_name (
id,
lastname,
firstname
)
VALUES (
e7ae5cf3-d358-4d99-b900-85902fda9bb0,
'FRAME',
'Alex'
);
The below is the trace log
Tracing session: 9b378c70-b114-11e6-89b5-b7fad52e1885
activity | timestamp | source | source_elapsed | client
-----------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------+-----------+----------------+-----------
Execute CQL3 query | 2016-11-22 16:34:34.300000 | 127.0.0.1 | 0 | 127.0.0.1
Parsing INSERT INTO cycling.cyclist_name (id, lastname, firstname) VALUES (e7ae5cf3-d358-4d99-b900-85902fda9bb0, 'FRAME','Alex'); [Native-Transport-Requests-1] | 2016-11-22 16:34:34.305000 | 127.0.0.1 | 5935 | 127.0.0.1
Preparing statement [Native-Transport-Requests-1] | 2016-11-22 16:34:34.308000 | 127.0.0.1 | 9199 | 127.0.0.1
Determining replicas for mutation [Native-Transport-Requests-1] | 2016-11-22 16:34:34.330000 | 127.0.0.1 | 30530 | 127.0.0.1
Appending to commitlog [MutationStage-3] | 2016-11-22 16:34:34.330000 | 127.0.0.1 | 30979 | 127.0.0.1
Adding to cyclist_name memtable [MutationStage-3] | 2016-11-22 16:34:34.330000 | 127.0.0.1 | 31510 | 127.0.0.1
Request complete | 2016-11-22 16:34:34.333633 | 127.0.0.1 | 33633 | 127.0.0.1
Reference link: https://docs.datastax.com/en/cql-oss/3.3/cql/cql_reference/cqlshTracing.html

Can´t save files using ftp on genexus

I am trying to save a file on a library inside a Iseries database using the GxFtpPut on genexus 10 V3 with .net but when sending the file genexus tries to send it to a windows directory instead of sending it to the library which works using the ftp command on the cmd
I've already tried to changing the route is using to no avail and trying to find another way of sending the file through genexus.
for example when using the cmd I just put this :
put C:\FILES\Filename.txt Library/Filename
And it works on sending the file inside the library,
but when doing this on genexus:
Call("GxFtpPut", &FileDirectory , 'Library/'+&FileName,'B' )
Does not work and tries to find a directory with that name inside the windows files of the server
I just want to be able to send it to the server library without issue.
IBM i has two distinct name formats depending on the file system you are trying to use. NAMEFMT 0 is the library/filename format, and is likely unknown to PC FTP clients. NAMEFMT 1 is the typical hierarchical directory path used by non-IBM i computers, and also works with IBM i if you want to put a file anywhere in the IFS (Integrated File System).
Fun fact, the native library file system is also accessible from the IFS. But to address it you need to use a format that might be a little unfamiliar. /QSYS.lib/library.lib/filename.file/membername.mbr You may be able to drop the member name.
To change name format, you can issue the SITE sub-command on your remote host like this:
QUOTE SITE NAMEFMT 0 -- This sets name format 0 (library/filename)
QUITE SITE NAMEFMT 1 -- This sets name format 1 (directory path)
I did some testing with a plain Windows FTP client. The test file on the PC was a text file created in Notepad++. Turns out that we start out in NAMEFMT 0 unless it is changed. It looks like genexus only supports a limited set of commands. So here is the limited FTP script that works:
ascii
put test.txt mylib/testpf
I can now pull up testpf on the greenscreen utilities and read it. I can also read testpf in my GUI SQL client. The ASCII text has been converted properly to EBCDIC.
|TESTPF |
|--------------------------------------------------------------------------------|
| |
|// ------------------------------------ |
|// Sweep |
|// |
|// Performs the sweep logic |
|// ------------------------------------ |
|dcl-proc Sweep; |
| |
| |
| exec sql |
| update atty a |
| set ymglsb = (select ymglsb from glaty |
| where atty = a.atty) |
| where atty in (select atty from glaty where atty = a.atty); |
|// where ymglsb in (select ymglsb from glaty where atty = a.atty); |
| if %subst(sqlstate: 1: 2) < '00' or |
| %subst(sqlstate: 1: 2) > '02'; |
| exec sql get diagnostics condition 1 |
| :message = message_text; |
| SendSqlMsg('02: ' + message); |
| endif; |
| |
| exec sql |
| update atty a |
| set ymglsb = '000' |
| where not exists (select * from glaty where atty = a.atty); |
| if %subst(sqlstate: 1: 2) < '00' or |
| %subst(sqlstate: 1: 2) > '02'; |
| exec sql get diagnostics condition 1 |
| :message = message_text; |
| SendSqlMsg('03: ' + message); |
| endif; |
| |
|end-proc; |
However, if I try to transfer in binary mode, the resulting data in the file looks like this:
|TESTPF |
|--------------------------------------------------------------------------------|
|ëÏÁÁø&ÁÊÃ?Ê_ËÈÇÁËÏÁÁø% |
|?ÅÑÄÀÄ%øÊ?ÄëÏÁÁøÁÌÁÄËÉ% |
|ÍøÀ/ÈÁ/ÈÈ`/ËÁÈ`_Å%ËÂËÁ%ÁÄÈ`_Å%ËÂÃÊ?_Å%/È` |
|ÏÇÁÊÁ/ÈÈ`//ÈÈ`ÏÇÁÊÁ/ÈÈ`Ñ>ËÁ%ÁÄÈ/ÈÈ`ÃÊ?_Å%/È`ÏÇÁÊÁ/ÈÈ |
|`//ÈÈ`ÏÇÁÊÁ`_Å%ËÂÑ>ËÁ%ÁÄÈ`_Å%ËÂÃÊ?_Å%/È`ÏÇÁÊÁ/ÈÈ`//ÈÈ |
|`ÑöËÍÂËÈËÉ%ËÈ/ÈÁ?ʶËÍÂËÈËÉ%ËÈ/ÈÁ |
|ÁÌÁÄËÉ%ÅÁÈÀÑ/Å>?ËÈÑÄËÄ?>ÀÑÈÑ?>_ÁËË/ÅÁ_ÁËË/ÅÁ¬ÈÁÌÈ |
|ëÁ>ÀëÉ%(ËÅ_ÁËË/ÅÁÁ>ÀÑÃÁÌÁÄËÉ%ÍøÀ/ÈÁ/ÈÈ`/ |
|ËÁÈ`_Å%ËÂÏÇÁÊÁ>?ÈÁÌÑËÈËËÁ%ÁÄÈÃÊ?_Å%/È`ÏÇÁÊÁ/ÈÈ`// |
|ÈÈ`ÑöËÍÂËÈËÉ%ËÈ/ÈÁ?ʶËÍÂËÈËÉ%ËÈ/ÈÁ |
|ÁÌÁÄËÉ%ÅÁÈÀÑ/Å>?ËÈÑÄËÄ?>ÀÑÈÑ?>_ÁËË/ÅÁ_ÁËË/ÅÁ¬ÈÁÌÈ |
|ëÁ>ÀëÉ%(ËÅ_ÁËË/ÅÁÁ>ÀÑÃÁ>ÀøÊ?Ä |
This has not been converted because we have told IBM i FTP server not to convert to EBCDIC because it is binary.
So try ASCII mode, use the library/filename format. The target file does not need to pre-exist.

Moving dev site to production on new account AWS

I am in the process of moving and testing a development site on the actual domain name now and I just wanted to check if I was missing anything and also get some advice.
It is a Magento 1.8.1 install from Turnkey Linux running on an m1.medium instance.
What I have done (so far) is, create an image of the development instance, made a new account and copied it over to there. I then made an elastic IP and associated it with the new instance. Next I pointed the A name record of the production domain to the elastic IP.
Now, if I go to the production domain I get redirected to the development domain. Is there a reason for this?
Ideally I would like to have two instances, one dev one that is off unless needed and of course the production on which is going to be live 24/7. However if I turn the development domain off it stops the other too.
I have a feeling it's just because I need to change instances of the dev domain in the Magento database / back-end however I wanted to get a more knowledgable answer as I don't want to break either of the instance.
Also, I should probably mention that the development domain is a subdomain i.e. shop.mysite.com and the live one is just normal i.e. mysite.com. Not entirely sure this is relevant but thought it worth a mention.
Thanks in advance for any help.
The reason your URL on your new instance is getting redirected to the old URL is because in the core_config_data table of your magento database the web/unsecure/base_url and web/secure/base_url paths point to your old URL.
So if you are using mysql you can query your database as follows:
mysql> use magento;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from core_config_data;
+-----------+---------+----------+-------------------------------+-------------------------------------+
| config_id | scope | scope_id | path | value |
+-----------+---------+----------+-------------------------------+-------------------------------------+
| 1 | default | 0 | web/seo/use_rewrites | 1 |
| 2 | default | 0 | admin/dashboard/enable_charts | 0 |
| 3 | default | 0 | web/unsecure/base_url | http://magento.myolddomain.com/ |
| 4 | default | 0 | web/secure/use_in_frontend | 1 |
| 5 | default | 0 | web/secure/base_url | https://magento.myolddomain.com/ |
| 6 | default | 0 | web/secure/use_in_adminhtml | 1 |
| 7 | default | 0 | general/locale/code | en_US |
| 8 | default | 0 | general/locale/timezone | Europe/London |
| 9 | default | 0 | currency/options/base | USD |
| 10 | default | 0 | currency/options/default | USD |
| 11 | default | 0 | currency/options/allow | USD |
| 12 | default | 0 | general/region/display_all | 1 |
| 13 | default | 0 | general/region/state_required | AT,CA,CH,DE,EE,ES,FI,FR,LT,LV,RO,US |
| 14 | default | 0 | catalog/category/root_id | 2 |
+-----------+---------+----------+-------------------------------+-------------------------------------+
14 rows in set (0.00 sec)
and you can change it as follows:
mysql> update core_config_data set value='http://magento.mynewdomain.com' where path='web/unsecure/base_url';
mysql> update core_config_data set value='https://magento.mynewdomain.com' where path='web/secure/base_url';

Communication between two applications using Environment Variables

Question
How to communicate with another program (for instance, a windows service one) through environment variables (not system or user ones)?
What do we have
Well, I have the following scheme for a data logger:
------------------------- --------------------------------
| the things to measure | | the things that do something |
------------------------- --------------------------------
| ^
| sensors | switches
V |
-------------------------------------------------------------------
| dedicated hardware |
-------------------------------------------------------------------
| ^
| | serial communication
V |
--------------- -------------
| Windows | ------------------------------------> | user |
| service | <------------------------------------ | interface |
--------------- udp communication -------------
|^ keyboard
V| and screen
--------
| user |
--------
On current development:
windows service is always running when Windows is running
user can open and close user interface (of course :p)
windows service acquires data from sensors
user interface automatic requests data to windows service every 100ms and shows it to user via udp communication through some implemented protocol (we call it GetData() command and response to it)
user can send some other commands to change the data to acquire through implemented protocol (we call it SetSensors() command and response to it)
Both user interface and windows service are developed on Borland C+ Builder 6 and use NMUDP component, from FastNet tab, for UDP communication.
What we are thinking to do
Because of some buffer issues and to free udp channel only for sending SetSensors()command and response to it, we are considering that instead of using GetData():
Windows service would get data from sensors and put them on environment variables
the user interface would read them to show to user
Scheme after doing what we are thinking
------------------------- --------------------------------
| the things to measure | | the things that do something |
------------------------- --------------------------------
| ^
| sensors | switches
V |
-------------------------------------------------------------------
| dedicated hardware |
-------------------------------------------------------------------
| ^
| | serial communication
V |
--------------- -------------
| | ------------------------------------> | |
| | environment variables | |
| | (get data from sensors) | |
| Windows | | user |
| service | | interface |
| | | |
| | ------------------------------------> | |
| | <------------------------------------ | |
--------------- udp communication -------------
(send commands to service) |^ keyboard
V| and screen
--------
| user |
--------
Any way to do that?
We would not use system and user environment variables, because it writes on Windows Registry, i.e., it will save to hard drive and it gets more slow...
As #HansPassant said, I cannot do that directly. Although I saw some ways to do that via memory mapped file, it is so easy only to add one more udp communication channel through other port. So:
------------------------- --------------------------------
| the things to measure | | the things that do something |
------------------------- --------------------------------
| ^
| sensors | switches
V |
-------------------------------------------------------------------
| dedicated hardware |
-------------------------------------------------------------------
| ^
| | serial communication
V |
--------------- -------------
| | ------------------------------------> | |
| | udp communication (port 3) | |
| | (get data from sensors) | |
| Windows | | user |
| service | | interface |
| | (port 1) | |
| | ------------------------------------> | |
| | <------------------------------------ | |
--------------- udp communication (port 2) -------------
(send commands to service) |^ keyboard
V| and screen
--------
| user |
--------
If someone provide a better solution, I'll mark it as solution in future.

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