I try to connect to my router using ssh in order to automatically extract some logs from it.
I developed this code below :
#!/usr/bin/expect -f
spawn ssh root#192.168.1.1
expect "Are you sure you want to"
send -- "yes\r"
expect "password"
send -- "root\r"
expect "\#"
send -- "ls\r"
expect "\#"
the problem is I expected a garbage before the prompt in the output log.
spawn ssh root#192.168.1.1
The authenticity of host '192.168.1.1 (192.168.1.1)' can't be established.
RSA key fingerprint is SHA256:6aeE74qXMeQzg0SGJBZMIa0HFQ5HJrNqE5f3XZ6Irds.
Are you sure you want to continue connecting (yes/no)? yes
Failed to add the host to the list of known hosts (/home/amin/.ssh/known_hosts).
root#192.168.1.1's password:
BusyBox v1.30.1 () built-in shell (ash)
OpenWrt Version: ALPHA
OpenWrt base: 19.07
------------------------------------
]0;root#openwrt: ~root#openwrt:~# ls
[0;0mnetwork[m
]0;root#openwrt: ~root#openwrt:~#
what's the main cause of this issue? How I can fix it?
The problem is that there are terminal escape sequences being issued, probably to control what colour the terminal uses. The easiest fix is to set the terminal type (an environment variable) to something that doesn't support colour before doing the spawn. Perhaps this will do the trick:
set env(TERM) "dumb"
If that doesn't work (it depends on exactly what is in someone's .bashrc) then you can just override the PS1 environment variable on the remote side with your first command after logging in.
# etc for logging in
expect "# "
send "PS1='# '\r"
expect "# "
# Everything should be right from here on
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
I am trying to write an expect script that will do the following..
open up 13 terminal windows (gnome-terminal, xterm etc)
each window connects to a terminal server via ssh (ssh InReach#10.1.6.254)
and is provided the password via expect.
i can get this to work fine in a single window. the problem i am having though is getting the input passed over to each window.
for instance...
i can do
set timeout -1
spawn gnome-terminal -x ssh InReach#10.1.6.254
inside of a while loop and get my 13 windows. but i would like each one to be logged in automatically via expect.
You can try a slightly different approach. Instead of opening the terminal windows in the expect script, open them in a basic shell script, and have each terminal run an expect script to start a single SSH session.
So the expect script could be as simple as this:
#!/usr/bin/expect -f
spawn ssh InReach#10.1.6.254
# ... provide password ...
interact
And the shell script:
#!/bin/sh
for a in `seq 1 13`; do
gnome-terminal -x ./expect_script
done
When you spawn, you need to cache the $spawn_id value which is set by the attempt.
e.g.
if [catch "spawn ssh -l mtc $ub1_ip_address" ub1_pid] {
Log $ERROR "Unable to spawn ssh to Xubuntu.\n$ub1_pid\n"
return 0
}
set stored_id $spawn_id
To send a command to one terminal session in particular, do
send -i $stored_id "command"
Then, before you contact each, you must first do
expect {
-i $stored_id
[ ... your regexes, globs, etc. ... ]
}
You can find some add'l info http://wiki.tcl.tk/11583
I would also suggest making use of gnome-terminal's ability to specify multiple tabs, including an indication of which is the currently-active one, and a command to be executed. gnome-terminal --help-all is helpful (no pun intended).
It is possible that my question title is misleading, but here goes --
I am trying out a prototype app which involves three MySQL/Perl Dancer powered web apps.
The user goes to app A which serves up a Google maps base layer. On document ready, app A makes three jQuery ajax calls -- two to app B like so
http://app_B/points.json
http://app_B/polys.json
and one to app C
http://app_C/polys.json
Apps B and C query the MySQL database via DBI, and serve up json packets of points and polys that are rendered in the user's browser.
All three apps are proxied through Apache to Perl Starman running via plackup started like so
$ plackup -E production -s Starman -w 10 -p 5000 path/to/app_A/app.pl
$ plackup -E production -s Starman -w 10 -p 5001 path/to/app_B/app.pl
$ plackup -E production -s Starman -w 10 -p 5002 path/to/app_C/app.pl
From time to time, I start getting errors back from the apps called via Ajax. The initial symptoms were
{"error":"Warning caught during route
execution: DBD::mysql::st fetchall_arrayref
failed: fetch() without execute() at
<path/to/app_B/app.pm> line 79.\n"}
The offending lines are
71> my $sql = qq{
72> ..
73>
74>
75> };
76>
77> my $sth = $dbh->prepare($sql);
78> $sth->execute();
79> my $res = $sth->fetchall_arrayref({});
This is bizarre... how can execute() not take place above? Perl doesn't have a habit of jumping over lines, does it? So, I turned on DBI_TRACE
$DBI_TRACE=2=logs/dbi.log plackup -E production -p 5001 -s Starman -w
10 -a bin/app.pl
And, following is what stood out to me as the potential culprit in the log file
> Handle is not in asynchronous mode error 2000 recorded: Handle is
> not in asynchronous mode
> !! ERROR: 2000 CLEARED by call to fetch method
What is going on? Basically, as is, app A is non-functional because the other apps don't return data "reliably" -- I put that in quotes because they do work correctly occasionally, so I know I don't have any logic or syntax errors in my code. I have some kind of intrinsic plumbing errors.
I did find the following on DBD::mysql about ASYNCHRONOUS_QUERIES and am wondering if this is the cause and the solution of my problem. Essentially, if I want async queries, I have to add {async => 1} to my $dbh-prepare(). Except, I am not sure if I want async true or false. I tried it, it and it doesn't seem to help.
I would love to learn what is going on here, and what is the right way to solve this.
How are you managing your database handles? If you are opening a connection before starman forks your code then multiple children may be trying to share one database handle and are confusing MySQL. You can solve this problem by always running a DBI->connect in your methods that talk to the database, but that can be inefficient. Many people switch over to some sort of connection pool, but I have no direct experience with any of them.
How can I trace MySQL queries on my Linux server as they happen?
For example I'd love to set up some sort of listener, then request a web page and view all of the queries the engine executed, or just view all of the queries being run on a production server. How can I do this?
You can log every query to a log file really easily:
mysql> SHOW VARIABLES LIKE "general_log%";
+------------------+----------------------------+
| Variable_name | Value |
+------------------+----------------------------+
| general_log | OFF |
| general_log_file | /var/run/mysqld/mysqld.log |
+------------------+----------------------------+
mysql> SET GLOBAL general_log = 'ON';
Do your queries (on any db). Grep or otherwise examine /var/run/mysqld/mysqld.log
Then don't forget to
mysql> SET GLOBAL general_log = 'OFF';
or the performance will plummet and your disk will fill!
You can run the MySQL command SHOW FULL PROCESSLIST; to see what queries are being processed at any given time, but that probably won't achieve what you're hoping for.
The best method to get a history without having to modify every application using the server is probably through triggers. You could set up triggers so that every query run results in the query being inserted into some sort of history table, and then create a separate page to access this information.
Do be aware that this will probably considerably slow down everything on the server though, with adding an extra INSERT on top of every single query.
Edit: another alternative is the General Query Log, but having it written to a flat file would remove a lot of possibilities for flexibility of displaying, especially in real-time. If you just want a simple, easy-to-implement way to see what's going on though, enabling the GQL and then using running tail -f on the logfile would do the trick.
Even though an answer has already been accepted, I would like to present what might even be the simplest option:
$ mysqladmin -u bob -p -i 1 processlist
This will print the current queries on your screen every second.
-u The mysql user you want to execute the command as
-p Prompt for your password (so you don't have to save it in a file or have the command appear in your command history)
i The interval in seconds.
Use the --verbose flag to show the full process list, displaying the entire query for each process. (Thanks, nmat)
There is a possible downside: fast queries might not show up if they run between the interval that you set up. IE: My interval is set at one second and if there is a query that takes .02 seconds to run and is ran between intervals, you won't see it.
Use this option preferably when you quickly want to check on running queries without having to set up a listener or anything else.
Run this convenient SQL query to see running MySQL queries. It can be run from any environment you like, whenever you like, without any code changes or overheads. It may require some MySQL permissions configuration, but for me it just runs without any special setup.
SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND != 'Sleep';
The only catch is that you often miss queries which execute very quickly, so it is most useful for longer-running queries or when the MySQL server has queries which are backing up - in my experience this is exactly the time when I want to view "live" queries.
You can also add conditions to make it more specific just any SQL query.
e.g. Shows all queries running for 5 seconds or more:
SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND != 'Sleep' AND TIME >= 5;
e.g. Show all running UPDATEs:
SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND != 'Sleep' AND INFO LIKE '%UPDATE %';
For full details see: http://dev.mysql.com/doc/refman/5.1/en/processlist-table.html
strace
The quickest way to see live MySQL/MariaDB queries is to use debugger. On Linux you can use strace, for example:
sudo strace -e trace=read,write -s 2000 -fp $(pgrep -nf mysql) 2>&1
Since there are lot of escaped characters, you may format strace's output by piping (just add | between these two one-liners) above into the following command:
grep --line-buffered -o '".\+[^"]"' | grep --line-buffered -o '[^"]*[^"]' | while read -r line; do printf "%b" $line; done | tr "\r\n" "\275\276" | tr -d "[:cntrl:]" | tr "\275\276" "\r\n"
So you should see fairly clean SQL queries with no-time, without touching configuration files.
Obviously this won't replace the standard way of enabling logs, which is described below (which involves reloading the SQL server).
dtrace
Use MySQL probes to view the live MySQL queries without touching the server. Example script:
#!/usr/sbin/dtrace -q
pid$target::*mysql_parse*:entry /* This probe is fired when the execution enters mysql_parse */
{
printf("Query: %s\n", copyinstr(arg1));
}
Save above script to a file (like watch.d), and run:
pfexec dtrace -s watch.d -p $(pgrep -x mysqld)
Learn more: Getting started with DTracing MySQL
Gibbs MySQL Spyglass
See this answer.
Logs
Here are the steps useful for development proposes.
Add these lines into your ~/.my.cnf or global my.cnf:
[mysqld]
general_log=1
general_log_file=/tmp/mysqld.log
Paths: /var/log/mysqld.log or /usr/local/var/log/mysqld.log may also work depending on your file permissions.
then restart your MySQL/MariaDB by (prefix with sudo if necessary):
killall -HUP mysqld
Then check your logs:
tail -f /tmp/mysqld.log
After finish, change general_log to 0 (so you can use it in future), then remove the file and restart SQL server again: killall -HUP mysqld.
I'm in a particular situation where I do not have permissions to turn logging on, and wouldn't have permissions to see the logs if they were turned on. I could not add a trigger, but I did have permissions to call show processlist. So, I gave it a best effort and came up with this:
Create a bash script called "showsqlprocesslist":
#!/bin/bash
while [ 1 -le 1 ]
do
mysql --port=**** --protocol=tcp --password=**** --user=**** --host=**** -e "show processlist\G" | grep Info | grep -v processlist | grep -v "Info: NULL";
done
Execute the script:
./showsqlprocesslist > showsqlprocesslist.out &
Tail the output:
tail -f showsqlprocesslist.out
Bingo bango. Even though it's not throttled, it only took up 2-4% CPU on the boxes I ran it on. I hope maybe this helps someone.
From a command line you could run:
watch --interval=[your-interval-in-seconds] "mysqladmin -u root -p[your-root-pw] processlist | grep [your-db-name]"
Replace the values [x] with your values.
Or even better:
mysqladmin -u root -p -i 1 processlist;
This is the easiest setup on a Linux Ubuntu machine I have come across. Crazy to see all the queries live.
Find and open your MySQL configuration file, usually /etc/mysql/my.cnf on Ubuntu. Look for the section that says “Logging and Replication”
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
log = /var/log/mysql/mysql.log
Just uncomment the “log” variable to turn on logging. Restart MySQL with this command:
sudo /etc/init.d/mysql restart
Now we’re ready to start monitoring the queries as they come in. Open up a new terminal and run this command to scroll the log file, adjusting the path if necessary.
tail -f /var/log/mysql/mysql.log
Now run your application. You’ll see the database queries start flying by in your terminal window. (make sure you have scrolling and history enabled on the terminal)
FROM http://www.howtogeek.com/howto/database/monitor-all-sql-queries-in-mysql/
Check out mtop.
I've been looking to do the same, and have cobbled together a solution from various posts, plus created a small console app to output the live query text as it's written to the log file. This was important in my case as I'm using Entity Framework with MySQL and I need to be able to inspect the generated SQL.
Steps to create the log file (some duplication of other posts, all here for simplicity):
Edit the file located at:
C:\Program Files (x86)\MySQL\MySQL Server 5.5\my.ini
Add "log=development.log" to the bottom of the file. (Note saving this file required me to run my text editor as an admin).
Use MySql workbench to open a command line, enter the password.
Run the following to turn on general logging which will record all queries ran:
SET GLOBAL general_log = 'ON';
To turn off:
SET GLOBAL general_log = 'OFF';
This will cause running queries to be written to a text file at the following location.
C:\ProgramData\MySQL\MySQL Server 5.5\data\development.log
Create / Run a console app that will output the log information in real time:
Source available to download here
Source:
using System;
using System.Configuration;
using System.IO;
using System.Threading;
namespace LiveLogs.ConsoleApp
{
class Program
{
static void Main(string[] args)
{
// Console sizing can cause exceptions if you are using a
// small monitor. Change as required.
Console.SetWindowSize(152, 58);
Console.BufferHeight = 1500;
string filePath = ConfigurationManager.AppSettings["MonitoredTextFilePath"];
Console.Title = string.Format("Live Logs {0}", filePath);
var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
// Move to the end of the stream so we do not read in existing
// log text, only watch for new text.
fileStream.Position = fileStream.Length;
StreamReader streamReader;
// Commented lines are for duplicating the log output as it's written to
// allow verification via a diff that the contents are the same and all
// is being output.
// var fsWrite = new FileStream(#"C:\DuplicateFile.txt", FileMode.Create);
// var sw = new StreamWriter(fsWrite);
int rowNum = 0;
while (true)
{
streamReader = new StreamReader(fileStream);
string line;
string rowStr;
while (streamReader.Peek() != -1)
{
rowNum++;
line = streamReader.ReadLine();
rowStr = rowNum.ToString();
string output = String.Format("{0} {1}:\t{2}", rowStr.PadLeft(6, '0'), DateTime.Now.ToLongTimeString(), line);
Console.WriteLine(output);
// sw.WriteLine(output);
}
// sw.Flush();
Thread.Sleep(500);
}
}
}
}
In addition to previous answers describing how to enable general logging, I had to modify one additional variable in my vanilla MySql 5.6 installation before any SQL was written to the log:
SET GLOBAL log_output = 'FILE';
The default setting was 'NONE'.
Gibbs MySQL Spyglass
AgilData launched recently the Gibbs MySQL Scalability Advisor (a free self-service tool) which allows users to capture a live stream of queries to be uploaded to Gibbs. Spyglass (which is Open Source) will watch interactions between your MySQL Servers and client applications. No reconfiguration or restart of the MySQL database server is needed (either client or app).
GitHub: AgilData/gibbs-mysql-spyglass
Learn more: Packet Capturing MySQL with Rust
Install command:
curl -s https://raw.githubusercontent.com/AgilData/gibbs-mysql-spyglass/master/install.sh | bash
If you want to have monitoring and statistics, than there is a good and open-source tool Percona Monitoring and Management
But it is a server based system, and it is not very trivial for launch.
It has also live demo system for test.