Chris Dutrow's questions

What is a good way to use a public domain name to access a server running on my laptop?

Note: My laptop's IP is not static and could be anywhere, at my apartment, in a coffee shop, tethered to my cell phone, etc...

Use Case

The use case is for debugging. Specifically for Amazon Lambda development where remote debugging does not really have support. I need external services such as Twilio and Slack to be able to trigger the debugging API instance so that I can set breakpoints and step through code.

Possible solutions

I've heard that something called a "DNS Tunnel" might be a good way. Or perhaps something like OpenVPN? I do not know enough about networking to know the right place to start with something like this.

Just had my website re-done and am trying to set up redirects in the .htaccess file for links that have changed

This works fine, except it doesn't work for /example/ (with trailing slash on source path)

Redirect 301 /example /example.php

So I added this to account for the trailing slash:

Redirect 301 /example/ /example.php

But that redirects to example.php/ (adds a trailing slash to the destination, which does not work)

Clearly I'm doing this wrong. What is a better way?

Have a web application at URL: EnterpriseJazz.com

I recently registered a shorter domain name: ejazz.cc in order to use as a url shortener.

I configured godaddy to forward the shorter ejazz.cc to EnterpriseJazz.com and it works fine for http (ie: I just typed ejazz.cc in the browser and EnterpriseJazz.com loaded without any problems)

When I tried to use it in in production with with an https url, the browser gave me the "Connection is not private" error.

Is there a way to change the configuration on GoDaddy to solve this or am I going to have to do something fancy with my SSL certificate?

Been trying to configure remote access and IPMI on this server, but the BIOS inexplicably does not have a space to configure an IP address. The screen shots in the manual show spaces for putting in the IP Address settings, and intuitively, they should be on this screen (Lan Settings menu).

Anyone run into a situation like this? I feel like there may be something off with the configuration elsewhere or perhaps even a jumper cable on the motherboard that needs to be adjusted?

More information

• This is from a Supermicro board: X8DTT-F

This is the screen shot from the manual:

Would like to back up my system configuration in Centos 7. What is a good way to do this?

Requirements

• There is no special data that needs to be backed up
• Would like to be able to save and restore to the state that the system was in after I spent all the time to install the OS, install other software, set up network and other configuration.
• Would prefer not to have to touch the actual server and instead use ssh or graphical interface through the VNC viewer I have set up.

There seem to be a lot of tools out there that could be used to do this, but I'm not sure which is the right one for Centos & and for this particular use case. I've looked into: timeshift, lvm snapshots, dump, and clonezilla SE.

I'm really not sure which of these, if any, I should apply to this use case?

Is it possible for some computers on a network to have their own public IP addresses and serve content over the internet while other computers on the same network only have private IP addresses but still have the ability to make requests over the internet (like a home computer would through a router)?

More information:

I have a group of 15 servers (and only 12 Public IP addresses available)

2 servers:

• Need to be able to server content over the internet
• Need to be able to make requests to the other 15 servers
• These servers are load balancers, they will forward requests to 4 other nginx servers that will server http content.

13 servers:

• Do not need to be able to serve content over the internet
• Need to be able to serve content the the other 15 servers
• Need to be able to make requests over the internet (to external APIs and such)
• 4 of these servers are nginx servers that will serve http content to the load balancers. They need to be able to make requests to external APIs (like google maps)

• 9 of these servers are database servers (they don't need to make requests to APIs, but it would be nice to be able to Teamviewer into them)

  • Is this possible?
  • Do I just need a layer 3 switch?
  • What do I need to look into in order to figure out how to do this?

Visual description of problem:

Have a cluster of desktop computers that are used to process data. Sometimes they crash and it would be nice of we could send a signal to the motherboards on them to restart the machine if we stop being able to connect via SSH.

Is there a piece of hardware that exists that can receive a signal signal via USB or serial port instructing it to connect two wires in the same way that pressing the "reset" button on a desktop case would?

In this way, the mechanism could be connected to the restart pins on another desktop's motherboard, and one computer could be used to restart another computer after it crashed. This seems like a pretty simple thing to do and I know I could do it with an arduino or something if I had the time, but seems like there should be something out there already that allows for this.

Thanks so much!

I apologize if this is a really dumb question.

Objective

Ensure that traffic that is meant to go between nodes in a cluster does not (inefficiently) go outside the cluster and then come back in, but goes directly between nodes.

Background

We are using external IP addresses when making requests that are intended to go between nodes.

The current architecture looks like this:

            Verizon FIOS ISP (Business, multiple static IPs)
                   |
                   |
            Verizon FIOS Router (Actiontec MI424WR)
            (Configured by forwarding external IPs to internal IPs using 
             Static NAT)
                   |
                   |
            Managed Swtich (Dlink DGS-1100-24)
               |      |      |      |
               |      |      |      |
            Node1   Node2   ...    Node(n)

Each node is running Linux Centos and is configured with an internal IP address (192.168.1.xxx)

The router is configured to route the external IP address that is assigned to each Node to the Node's internal IP address using Static NAT.

Concerns

• Can/Should I configure forwarding from external IP addresses to internal IP addresses in the switch?
• With the current configuration is the traffic between nodes getting directed to the correct node at the level of the switch, the router, or going all the way out to a DNS server or something?
• Considering that the router also converts the signal from the coaxial cable to ethernet, should I be using Static NAT or somehow configuring the Nodes themselves to have their external IP addresses. disregarding the need for internal IP addresses completely?
• Is there something completely different that I should be doing instead, or something else fundamentally wrong with this architecture?

Thanks so much!

Need to build a small business server cluster for the purpose of crunching data. It will not host a web site that needs to be available 24/7.

• It does need to support servers that host Redis, a Cassandra database cluster, and a Python web server. Operating system will most likely be Centos 6.4
• Other servers in the cluster should be able to communicate very fast with each other, especially the Redis server. This will probably require the use of internal IP addresses?
• We will need to use multi-data center replication to synchronize the Cassandra cluster with the one that we currently have hosted on the cloud

Was looking into network switches and we are unsure of the appropriate specifications that we should be looking for.

• Does the switch need to be "managed" or can it be "unmanged"?
• Does the switch need to support IPv6 or just IPv4?
• Do we need an enterprise level Cisco switch, or can we go with something like a $200 DLink managed (or unmanaged) small business switch?

Thanks so much!

Background:

Currently, we use Rackspace cloud servers. We have no intention to stop using them, but would like to look into setting up a cluster of physical servers (probably desktop computers in the $400 range with 8gb memory each) to offset some of our load and work as a secondary, more powerful, less reliable system. To put things in perspective, we can buy comparable desktop computers for the same price as we pay in one month to rent them on Rackspace Cloud.

I understand that this is generally a dumb idea. However, in this particular instance, the server cluster is needed for its computation power. It is not mission-critical, it does not host a consumer-facing website, and if it goes down for a day or two, its not really a problem.

Currently, we have access to business class verizon fios. If I understand correctly, we can get at least 25 dedicated IP addresses with this service, this should be enough.

Requirements:

• Each server runs Linux Centos 6.3
• Some of the servers run Python and execute processes from a task queue (Redis or RabbitMQ)
• Some of the servers are capable of serving static files and Python driven REST APIs
• Some of the servers host a Cassandra database cluster
• One or more of the servers are a Redis database servers
• One or more of the servers are PostgreSQL servers

Questions:

What kind of router or switch is needed?

• We would like the computers to be able to communicate effectively with each other via internal IP addresses. This is especially important for communicating with servers hosting Redis that need to be able to respond to requests very quickly. Are there special switches or routers that need to be used to connect the servers together?

Are Desktop computers ok for this?

• We have found that we are mostly RAM-bottle necked, I understand that some servers have highly superior CPUs, but I'm not sure we need CPU power as much as we need RAM, which is cheap in Desktop computers.
• Will we have problems with the WIFI cards in the desktops or any other unexpected hardware limitation?

What tools should be used to "image" the servers.

• For example, when we get an installation right for a Redis server or Cassandra node, are there tools that come with Linux Centos 6.3 to image the server to a USB drive or something like that?
• Or do we need to use some other software for this?

What other things are we missing that we should be concerned about?

Question:

Is there a way to use uWSGI as a proxy server?

More about the system:

• 6 load-balanced nginix/uWSGI servers
• Python

Requirements:

• Set up a few proxy servers that can:
  • Accept requests from a client browser
  • Read and modify request URL
  • Read and modify request headers
  • Forward request to another proxy server

The reason we would like to use uWSGI as the proxy server is because we are already using uWSGI with the application and all of our Python code will work it.

Right now, we use uWSGI to serve a RESTful http API with Python on the back end. As I understand it, a proxy server works differently than the REST API would.

Please forgive my ignorance, I know very little about proxy servers and how they work. I also realize that these requirements sound totally wacky, but I assure you, there is a rhyme and reason to it.

Thanks so much!

For development purposes, I'm running an Apache server on my windows machine. Its very non-critical, but sometimes I'll be running processes that take a long time and Apache will stop server requests. Restarting the Apache service works just fine when this happens.

Is there a script out there somewhere that can detect if Apache is failing to load pages and then restart the service if it is?

It would probably look something like this:

LOAD localhost/index.php
IF LOAD FAILED:
   RESTART APACHE SERVICE

I've been looking into Heroku as a hosting provider. I'm specifically interested in its ease of deployment and ability to scale up and scale down resources as needed.

Is there a hosting solution with this type of ease and power that works with Django?