Django Application and Apache Server with ERR_CONNECTION_RESET on AWS - django

I have a Django application running on two AWS EC2 instances with a load balancer. I am using Apache as a web application server.
As you can see below, if I run logistic regression on MagicStat using those 8 parameters and the banking.csv file, everything runs fine after clicking the Analyze button. If I use one more parameter, i.e. 9 parameters, I end up with ERR_CONNECTION_RESET error. Even when I run the application directly inside the server using the same Apache (http://localhost), it doesn't work either. Note that I make AJAX calls in each request such as selecting the model and clicking the Analyze button.
Interestingly, that doesn't happen, i.e. it works with those 9 parameters, if I run my Django application from local Apache server (http://localhost).
.
I don't know what is happening? Any suggestions?
Note: Running 9 parameters with the banking.csv file crashes my apache server, so that's the reason why I didn't share the data file here.

Okay, I've finally figured it out after almost 2 weeks of frustrating work. It was an AWS ec2 issue (t3.large). After I installed new ec2 instances (t2.large), it worked. I think something was wrong with the configurations of those ec2 instances.

Related

Using plink commands from Rstudio with the AWS EC2 has disabled the instance DNS

I was trying to process GWAS data using plink1.9 with a rental AWS ubuntu server. I executed the plink commands from the terminal window in the Rstudio server.
It turned out that if I execute a plink command that overloads the server, my Rstudio server will become inaccessible and this problem does not revolve.
for example my Rstudio-server from port 8787 has become unavailable.
http://ec2-54-64-41-xxx.ap-northeast-1.compute.amazonaws.com:8787/
I accidentally did it twice. First time I did something like cat xxx.vcf (how stupid of me) and the server simply went frozen and the Rstudio server crashed.
Since I could still access the server with putty and winscp and so on I managed to get my files to a new instance. Then I tried to use plink to do some QC, something like
./plink --bfile xxx--mind 1 --geno 0.01 --maf 0.05 --make-bed --out yyy
It had again overloaded the server and the same Rstudio server trouble occurred again.
Now both instances are still accessible from putty, I logged on to check the running processes and it seemed to be fine. There were no active heavy jobs and no zombie processes either.
The CPU monitoring looks fine too.
With the only problem that the Rstudio-server link is not working.
Does anyone have similar experiences? Your advice is very much appreciated.
mindy

Port mapping in Windows Server 2016 - Docker

I have been trying to setup Docker in Windows Server 2016 in an AWS instance to run an IIS program.
From this question,
Cannot access an IIS container from browser - Docker, IIS has been setup inside a container and it is accessible from the host without port mapping.
However, if I want to allow other users from the Internet/Intranet to access the website, after Google-ing it, I guess we do need port mapping...
The error I have encountered in port mapping is given in the above question so... I guess using nat is not the correct option. Therefore, my team and I tried to create another network (custom/bridge) following instructions from
https://docs.docker.com/v17.09/engine/userguide/networking/#user-defined-networks
However, we cannot create a network as follows:
; Googled answer:
https://github.com/docker/for-win/issues/1960
My team guessed maybe its because AWS blocked that option, if anyone can confirm me, please do.
Another thing that I notice is: when we create an ECS instance in AWS,
So... only default = NAT network mode is accepted in Windows server?
Our objective: put the container hosted IIS application to Internet/Intranet in Windows Server 2016...
If anyone has any suggestion/advice, please tell me, many thanks.

Spinnaker on AWS: Create application hangs

I'm having trouble creating a new application on Spinnaker after following the quickstart guide for AWS. The server runs fine on Port 9000 and I've enabled Port 8084 (via AWS Security Group) for Deck/Gate to run.
However, when I try to create a new project on the UI, the menu hangs like shown here.
I've tried configuring and running this setup several times now, however I cannot get past this part. Can someone help?
Thanks in advance.
So I worked on things some more and was able to fix my problem. I realized that Spinnaker needs Authentication set up as mentioned in this FAQ.
I opted to expose my Spinnaker to end users (likely to change in the near future). While I enabled Gate and Deck to listen on 0.0.0.0, I did not associate a domain name with them which caused things not to work. After associating them with a domain name, I was able to make a new application.

Suddenly scheduled tasks are not running in coldfusion 8

I am using Coldfusion MX8 server and one of the scheduled task was running from 2 years but now suddenly from 01/12/2014 scheduled tasks are not running. When i browsed the file in browser then the file is running successfully without error.
I am not sure is there any updatation or license expiration problem. I am aware that mid of this year Adobe closed the support for coldfusion 8.
The first most common problem of this problem is external to the server. When you say you browsed to the file and it worked in a browser, it is very important to know if that test was performed on the server desktop. Knowing that you can browse to the file from your desktop or laptop is of small value.
The most common source of issues like this is a change in the DNS or network stack that is interfereing with resolution. For example, if the internal DNS serving your DMZ suddenly starts serving the "external" address - suddenly your server can't browse to your domain. Or if the IP served by the server for the domain in question goes from being 127.0.0.1 to some other IP that the server can't acces correctly due to reverse proxy or LB or some other rule. Finally, sometimes the Apache or IIS is altered so that an IP that previously was serviced (127.0.0.1 being the most common example) now does not respond.
If it is something intrinsic to the scheduler service then Frank's advice is pretty good - especially look for "proxy schduler" entries in the log - they can give you good clues. I would also log results of a scheduled task to a file. Then check the file. If it exists then your scheduled tasks ARE running - they are just not succeeding. Good luck!
I've seen the cf scheduling service crash in CF8. The rest of CF is unaffected.
Have you tried restarting the server?
Here are your concerns:
Your File (works since you tested it manually).
Your Scheduled Task (failed).
Your Coldfusion Application (Service) (any changes here)?
Your Server (what about here).
To test your problem create a duplicate task and schedule it. Leave the other one in place (maybe set your new one to run earlier). Use the same file too. See if it completes.
If it doesn't then you have a larger problem. Since the Coldfusion Server sits atop of the JVM there could be something happening there. Things just don't stop working unless something got corrupted or you got compromised. If you hardened your server by rearranging/renaming the file structure to make it more secure...It would break your task.
So going back: if your test schedule works then determine what is different between the two. Note you have logging capabilities. Logging abilities for CF8
If you are not directly incharge of maintaining this server, then I would recommend asking around and see if there was recent maintenance, if so, what was done to the server?

jetty 404 error page on hot deployment

I am currently using Jetty 9.1.4 on Windows.
When I deploy the war file without hot deployment config, and then restart the Jetty service. During that 5-10 seconds starting process, all client connections to my Jetty server are waiting for the server to finish loading. Then clients will be able to view the contents.
Now with hot deployment config on, the default Jetty 404 error page shows within that 5-10 second loading interval.
Is there anyway I can make the hot deployment has the same behavior as the complete restart - clients connections will wait instead seeing the 404 error page ?
Unfortunately this does not seem to be possible currently after talking with the Jetty developers on IRC #jetty.
One solution I will try to use are two Jetty instances with a loadbalancing reverse proxy (e.g. nginx) before them and taking one instance down for deployment.
Of course this will instantly lead to new requirements (session persistence/sharing) which need to be handled. So in conclusion: much work to do in the Java world for zero downtime on deployments.
Edit: I will try this, seems like a simple enough solution http://rafaelsteil.com/zero-downtime-deploy-script-for-jetty/ Github: https://github.com/rafaelsteil/jetty-zero-downtime-deploy