EPiserver cache load balancer - caching

I have a strange problem with EpiServer 6.0 . When it is on the environment behind the load
balancer it seems to have out dated cache. For example when accessing user settings it doesn't bring the latest data however when run locally or when load balancer is not present I got the latest results. There is an event listener set-up between the two load balanced servers to update the cache. Could anybody advise please?

This article will probably be helpful to you.
First thing to check is that the enableEvents and enableRemoteEvents attributes are both set to “true” in the episerver.config file

Related

Ngnix Load Balancer unable to find if plus or open source

Hi I have recently joined a firm using ngnix. However, the old team and I are unsure if they are using ngnix plus or ngnix open source. Can anyone guide how to check if the ngnix load balancer we are using is plus or open source ?
Are there different versions or is there some other method.
Any help or suggestion would mean a lot.

In Weblogic 10.3.5, is there any way to expire an html file from cache without going through a server restart

In Weblogic 10.3.5, is there any way to expire an html file from cache without going through a server restart. I am supporting a server with frequent HTML changes and hoping to find a way not to restart the server each time the HTML is updated. Environment is supporting a PeopleSoft domain. Thanks.
There's a way indeed, the parameter "Resource Reload Check (in seconds)" which can be found on a web app setup is what you're looking for. I've setup this to 5(secondes) in order to have a periodic refresh on dynamic ressources generated by an application engine (an xml parsed by an xslt)
For some details here's doc of 12.1.2 but I confirm it exists also on 10.3.4 (so on your version too) : https://docs.oracle.com/middleware/1212/wls/WLACH/pagehelp/J2EEwebappwebappconfigurationtitle.html

Problems flushing Magento Redis Cache on an installation with a separate backend server

My problem is that I do not think I am able to refresh the magento redis cache from the admin page. I realize that the problem could come from many sources, but my gut tells me it has something to do with the backend being on a separate server. My magento installation is as follows:
Magento CE 1.8
Backend server and NFS(media) on an Amazon AWS EC2 at
http://admin.example.com
Database on AWS RDS MySQL 2 app servers
(scalable to more) on AWS Elastic Beanstalk at http://www.example.com
(route53)
regular backend cache(database 0), Lesti-FPC(database 0), and
redis_session (database 1) on AWS elasticache redis
I originally had my Lesti-FPC configured to use database 2 on the redis cache. I thought it worked pretty well as far as I could tell, until I realized that I couldn't flush the cache at all from the admin System>Cache Management page. "Flush Magento Cache," "Flush Cache Storage," "disable", and "refresh" did nothing. I could only flush it by rebooting the redis node or going in with redis-cli and using redis commands.
I then tried configuring Lesti-FPC to use database 0 as described above. It worked better. Now, I could flush the FPC with "Flush Cache Storage," although the other options still didn't work. At the time, I assumed it was an issue specifically with Lesti-FPC. But anyway, using "Flush Cache Storage" was good enough for me at the time, especially once I discovered that I could flush the cache through code using
Mage::app()->getCacheInstance()->flush();
I just recently found out that the problem may not be specific to Lesti-FPC. While trying to fix the Lesti issue, I tried monitoring redis. I know nothing about redis or caching, but when I would try to refresh the FPC, I would see commands like:
“del” “zc:ti:403_FPC”
“srem” “zc:tags” “403_FPC”
But those tags never existed. Doing:
keys *FPC*
in redis would give me
“zc:ti:109_FPC”
but nothing with 403. SO this means that my fpc caches do not get invalidated like they're supposed to after product/category changes and reindexing. I got around this by manually flushing the cache after changes and running cron jobs to flush and prime the fpc every few hours.
But it made me suspicious. I tried refreshing the other caches from the admin, and I found that magento would always try to delete and read the 403 keys(some of which existed and some of which did not) but never any 109 keys (of which there are many).
My guess is that the 403 keys are specific to the admin server, and the 109 keys are specific to the app servers. The admin server, maybe because it is on a different subdomain, is not touching the app servers' cached stuff. But the app servers are able to find its own keys fine, as demonstrated by the fact that the FPC is working very well.
Does this make sense? Is there something I could do to fix this? Did I configure something incorrectly or is this a magento bug?
It turns out that the Zend cache prefix is the first three characters of an md5 hash of the path to your etc folder.
My app server has its document root at /var/www/html. The full path of /var/www/html/app/etc gives an id of 403. The app servers running on elastic beanstalk have their document roots at /var/app/current which is done automatically at deployment.
It seems pretty dumb. Why not a hash of the database address and database name or something? That would make more sense.
Anyway, I hope this helps someone.

Autoscale Magento in the cloud

I have just entered into the world of e-commerce, and I am trying to get my Magento website up and running.
I am using AWS cloud for hosting my website. I am trying to use an architecture, where I can run multiple servers connected to a single DB server. Specifically, I want to use an AWS Auto scaling group along with ELB to start multiple EC2 instances, during high load. There is only one Mutli AZ RDS Database instance.
As initial trials, I tried creating 2 ec2 instances, and installed magento on both of them. I have used same RDS DB for both of them. But as is turns out, magento stores the base url of webserver in the database itself. Which means, I can only store one base url of magento website running one particular server.
To be precise magento stores base url in table core_config_data in column 'path' where row values ares "web/unsecure/base_url" and "web/secure/base_url", and the column 'value' for corresponding row specifies the url address of magento installed web server.
My question is how can I use multiple server using EC2 auto scaling, if magento permits only one server address in the base url.
Here's a partial view of the table with 2 rows -
config_id scope scope_id path value
5 default 0 web/unsecure/base_url http://server1.com/magento/
6 default 0 web/secure/base_url http://server1.com/magento/
Are there any other known methods to somehow use horizontal scaling during heavy load conditions in Magento.
I don't think load balancing works like that.
You need a load balancer that receives the requested URL and then passes it off to one of the servers running Magento - so I think you would pass the same url to both servers anyway, no?. I do not know how to do it.
You are trying to set up a very complicated system.
You could look to override some functions if you want to have different values for secure and non-secure urls. Try reading this code to get you started:
//file app/code/core/Mage/Core/Model/Store.php
//class Mage_Core_Model_Store
//function getBaseUrl()
//function getDistroServerVars()
//file app/code/core/Mage/Core/Model/Url.php
//class Mage_Core_Model_Url
//function getBaseUrl()
//file app/code/core/Mage/Core/Controller/Request/Http.php
//class Mage_Core_Model_Http
//function - I don't know, any of them, none of them
and look at any files with the string 'substDistroServerVars' in them or isDirectAccessFrontendName might expose something. getDistroServerVars is discussed at the end of this great article by the almighty Alan Storm.
But I don't think that is the real answer - for the real answer skip to the links at the end of this tedious monologue.
If this is your first foray into Magento and you really think you are going to get the volume of traffic into your shop that requires load balancing over two servers then you can afford, *must afford**, third party hosting and get professionals with many many many man years of experience running Magento on heavy loads across multiple servers. You will also want to hand off (at least) the images to a CDN.
*I mean, if your shop has that high a volume then it has a high revenue and you should invest that revenue in keeping your shop running: professional hosting with 24/7 support. Otherwise downtime will be expensive and a long implementation will mean lost revenue.
*If you are just trying this out for fun and to learn something about setting up Magento on multiple servers then I recommend two things:
1) Practice getting Magento running on one server first - and optimsing for volume there (caching, compilers, DB tuning, log file analysis, flat tables, cron jobs, CDNs, possibly combined JS and CSS, web server tuning and getting the headers right, possibly a full page cache and a sprinkling of Redis) - because that isn't a trivial list on one server never mind two + DB server and ELB.
And 2) practice getting Apache or nginx to serve load balanced content with your ecommerce SSL certificate in place. Only then should you try to join the two systems. Be prepared to spend many months on this - including figuring out Seige, AB or jmeter for simulated load testing.
But if you really want to get the AWS ELB set up here are a few excellent resources to get you started - particularly the detailed tutorial by Adrian Duke (first link) - pay great attention to the details in the last section of that article subtitled 'Magento', that may be the answer to your question.
Getting and scaling Magento in the cloud by Adrian Duke
Using AWS Auto Scaling with an Elastic Load Balancer cluster on EC2 (actually a WordPress install, not Magento, but Mr Shroder knows his Magento)
Running Magento in an AWS Environment (All hail Alan Storm)
I've had a rather large amount of success modifying the Magneto to be a beanstalk package. The steps (loosely) were:
Install GIT locally
Install AWS Command line tools
Install AWS Beanstlalk Command Line
Build module to upload image to s3 everytime it's uploaded in magento
Utilize OnePica's Magneto Extension
Use Amazon's REDIS Cache for caching data
Use RDS for database
Use Route53 for routing &
Use cloudfront for image, js & CSS Distro
Couple of drawbacks to AWS
Customizing magneto to look for things is a pain in the ass. As we speak I'm trying to get it to keep sessions persistent between EC2 instances as the loadbalancer chops it up.
Everytime you need to modify Magento in any way it's a git commit, (then we test locally, via a seperate beanstalk instance) and then push to production.
Short of that it's been fairly stable. We're not hitting high numbers yet, though.
Normally you put a load balancer in front of the nodes to distribute the load and each node is configured to use the same base_url. MySQL replication can be used if you want multiple db servers but I have never found the need to do this. Not used amazon ec2 with magento but have similar setup in a dedicated server environment with two nodes, one db server, load balancer, and shared media.
Diagram here is useful, especially with the shared storage for media, your going to need to do something like this. http://www.severalnines.com/blog/how-cluster-magento-nginx-and-mysql-multiple-servers-high-availability
Also, I found amazon seems to provide Elastic Load Balancing which is what your after I think. http://aws.amazon.com/documentation/elasticloadbalancing/

Liferay Community Edition centralized/shared storage issue

For quite some time I've been working on getting the community version of Liferay 6.0.6 (windows 2003 + Apache Httpd 2.2 + Apache Tomcat 6.0.29 ) to run on shared storage environment. Only the application base (webapps) is currently running from the shared storage. But I also wanted to move the "data" and "deploy" directory to the shared storage. So please provide any custom settings/changes that needs to be performed to change the location of these two directories/folders.
Whenever I change the "deploy destination directory" some portlets work, but not all (Custom portlets). It'll be great if anybody can provide certain points/checklist which needs to be followed in this situation.
Additionally, the configurations files used are attached along with this thread. If any other files is needed please let me know the same.
Thank you for your support in advance. All efforts are appreciated.
Thanks,
Joji VJ
Try to set Cache Page Definition Only at System Level,
By using this option create a single cached copy of the page definition in the system cache for all users.
Because the page definition is the same for all users, page customization options are disabled. This caching option greatly reduces storage requirements and improves performance.

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