user80666's questions

I'm using nginx to rewrite a url

rewrite ^/old$ /new1 permanent;

I need to change the address that /old redirects to (/new1) every few days. I noticed that when I change the /new1 url to /new2 and restart nginx, browser still redirects to /new1 untill I clear browser cache.

How can I prevent browser from cacheing redirection url?

P.S. The reason I need to keep changing the url is that I have a banner set up on one of the sites and in order to not bother the site owner with new url all the time, I though I'd give him one address to use and keep changing my redirection myself.

How do I redirect:

/text1 to /

and

/test2 to /something/else

I tried putting:

rewrite ^ /test1 /
rewrite ^ /test2 /something/else

Inside the server {}

I have setup a backup server which pulls data using rsnapshot from my server. rsnapshot is running as root on backup machine and connects to the server via RSA key that has no passphrase. My concern is that this may not be a good securitywise. If attacker gains access to my backup machine, he can compromise my backups and server data too.

The question is How should I do this right?

Another thing I'd like to know is:

How can I track rsnapshot activity, to make sure backup successfully finished and there were no problems?

I'm trying to optimize my apache and nginx installations and have been looking for information on how to setup correct number or min/max servers and connections in Apache and worker processes in Nginx.

I was wondering whether or not Apache and Nginx take advantage of multy core processors and how to set configuration in Apache and Nginx?

For example, lets say I have a 4 core processor, should I set workers to 4 in nginx? what should I set spare server in apache to?

I have Dropbear sshd running instead of openssh. Looks like there is /etc/ssh/ config dir full of files but they do not seem to be used by dropbear. I wanted to disable root login, anyone know how?

I have a NginX vhost, where all static content is served by nginx and anything that's not found or ends with php proxies to apache.

Just wanted to check if I have locations right:

location / {
  try_files $uri $uri/ @proxy;
  expires 30d;
}

location ~* \.php$ {
   proxy_pass      http://127.0.0.1:8080;
} 

location @proxy {
   proxy_pass      http://127.0.0.1:8080;
}

I was also wondering if there is a way to make second location go to third so that I do not have to repeat the proxy_pass line twice?

I have few other questions:

• Does nginx read locations from top to bottom and does it stop looking at next location if curent request matches one of the locations? For example, if server.com/image.jpg is requested, does it mean the very first location declaration will capture it in my locations, and rest will be ignored?

• If I do expires max; or expires 30d; but then site is updated and I want to force user browsers to reload the file right away, is there anything I can do to make them reload?

• my very first location declaration will match anypath that ends with .js, .css, .png and so on, but is it case sensitive? will it also match .PNG ? Should I make it case sensitive or not? If yes, how?

• Is there anything else you think would improve this configuration?

I have following python script, and want to run it with cron so that every minute cron will popup a message.

#!/usr/bin/python
# -*- coding: utf-8 -*-

import gtk.gdk
import pynotify
import random

m=[]
m.append("test1")
m.append("test2")
m.append("test3")

n = pynotify.Notification(random.choice(m))
n.set_hint('x', gtk.gdk.screen_width()/2.)
n.set_hint('y', gtk.gdk.screen_height()/2.)
n.show()

This is my cron script:

* * * * * export DISPLAY=:0.0 && /home/user/scripts/notifications.py >/dev/null 2>&1

Unfortunately nothing happens. Can you help please?

What's the most appropriate way to backup Mysql databases? I would like to have the backups in at least 1 hour intervals. I though mysqldump was the only option but It turns out there are other options too, like binary logs.

I would like to know how "big guys do it"

My tables are innodb would like to have backups as often as possible (at least every hour)

I gues even 1 hour intervals is not a perfect solution, since I would still use the changes after last backup, up to 1 hour.

I'm creating MySQL dump of 5 databases every hour. 3 of those databases very rarely change, so creating a MySQL dump for those 3 dbs is pretty much a waste of time and resources.

Is there a way I can retrieve a unix epoch seconds of when a specific db was last changed/updated? I would compare it with latest dump file and only dump another one if there are changes.

So question again: How can I get the unix epoch datetime of last update/change of a specific database?

In Bash script, I would like to compare two dates and if one is greater than the other, carry out a task.

Two dates that I'm comparing are:

svn repo's last change date, I get the date info like so:

svn info svn://server.com/reponame -r 'HEAD' | grep 'Last Changed Date'

It gives me something like this:

Last Changed Date: 2011-06-06 22:26:50 -0400 (Mon, 06 Jun 2011)

Then I'm finding the date information of the most current backup file in the directory, like so:

ls -lt --time-style="+%Y-%m-%d %H:%M:%S" | head -n 2 | tail -n 1

(I wonder if there is a better way to do it with out both head and tail above)

Which gives me something like this:

-rw-r--r-- 1 user1 user1 14 2011-06-09 07:52:50 svn.dump

What I would like to do next, is to retrieve date from first output and compare it with second output date and if one is greater than the other one, I will do an svn dump. what would be the most appropriate way to do this?

Thanks.

Is bounced email same as Delivery status notificaiton Failure or are those two different things?

I need to install Postfix or Exim to be able to send emails from my web server's php code. I have a few questions hopefully I can find answers to:

• Could mail be rejected or sent to spam on receiveing server if hostname of my machine is myhost.mydomain.com but I'm setting sender's email to [email protected]? What should I do? Should I just set my hostname to mydomain.com? Will this conflict with google apps in some way?

• What will happen to bounced mail on a setup where I have not really configured incoming email and incoming email is handled by Google apps? Could this cause delivery problems?

Note: My google apps is setup to accept mail for [email protected], but my hostname of sender machine is myhost.mydomain.com. I will be sending emails from my server as [email protected]. If sent email bounces, will it go to Google or my server?

• Is it absolutely necessary to have SPF and DKIM configured with my ourgoing mail or not to ensure delivery?

I need a bit of info on how all this works and how it should be set up properly and I appreciate your help. Thank you in advance.

should I run nginx for static content on port 81 or set it up as reverse proxy to apache?

Which is a better idea and why? I'm currently simply running nginx on port 81. i was wondering if there are any benefits as running it on port 80 instead and proxy to apache that sits on 8080 for example?

The title pretty much sums it up. Do I need to have a default vhost in Apache or Nginx?

On my website, users have files so I create a folder for each user when they register.

for example

/userdata/USERID

If site grows and I have thousands of users I might end up having too many user folders in one folder so i decided to split them up.

for example

/userdata/1/USERID (first thousand users)

/userdata/2/USERID (second thousand users)

My questions is how much folders should I put in one subfolder? Is 1000 in each a good idea? more? less? Just want to make sure things run smoothly.