Hi, We are utilizing citrix netscalar with more than 20 glassfish java application servers. Unfortunately we have to remove previous application before deploying a new version of it since we have same context for these two different application. This error-prone process leads some problems due to lack of attention in builds or other pro...
This is a question about k-means clustering algorithm. I have the following points and clustering of data S1. Can anyone tell me how to calculate the total error associated with this clustering? I know it's not a strictly programming question, but I need it for my algorithm. I think the answer should be 4/3 but I have no idea how to calc...
"This website is temporarily unavailable. Please check back later. Unfortunately there were no suitable nodes available to serve this request." When I request a stored procedure from my program (SP is taking 2 minutes to execute) the above error is getting. I believe this is because of Load balancer Time out. How we can increment the l...
Hi, I am looking to build a publish/subscribe distributed messaging framework that can manage huge volumes of message traffic with some intelligence at the broker level. I don't know if there's a topology that describes this, but this is the model I'm going after: EXAMPLE MODEL A A) There are two running message brokers (ideally all ...
We're trying to add some kind of persistence in our app. The app generates about 250 entries per second. Each of these entries belong to one of 2M files. For each file, we want to keep the last 10 entries, so we can look them up later. The way our client application works : it gets a stream of all the data it fetches the right file (...
How can I get a timer task on a WebSphere cluster to execute once and only once? I know this is possible on other app servers but can't figure out how to do this in WebSphere. ...
Hi there, fellows. I'm a total unix-way guy, but now our company creates a new application under ASP.NET + SQL Server cluster platform. So I know the best and most efficient principles and ways to scale the load, but I wanna know the MS background of horizontal scaling. The question is pretty simple – are there any built-in abilities...
Can you help me understand Linux HA? Pacemaker, Heartbeat, Corosync seem to be part of a whole HA stack, but how do they fit together? How does wackamole differ from Pacemaker/Heartbeat/Corosync? I've seen opinions that wackamole is better than Heartbeat because it's peer-based. Is that valid? The last release of wackamole was 2.5 ye...
Hi to all, I am hoping someone can give me pointers as to where I'm going wrong with clustering 3 servers with MySQL Cluster 7.1 with multiple management nodes. Currently, the cluster works perfectly with one management node. This is the setup: First server runs only an instance of ndb_mgmd (192.168.66.114) Second server runs an insta...
Hi to all. First off, I'm new to MySQL Cluster. This is my pain: I've managed to setup a MySQL Cluster with two data nodes, two SQL nodes and one management server. Everything works pretty well, except the following: my data nodes are spread across an intranet link which incurs latency into communications between the data nodes. Apparent...
If any database spreads across multiple servers (ex. Microsoft Sql Server), how can we do join or filter operations. In my scenario, if suppose: A single table spreads across multiple servers how can we filter rows based on user input? If master table is there on one db server and transaction table is at another db server, how can we d...
Hi, I'm trying to compute clusters on a set of points in Python, using GeoDjango. The problem: Given a set of points, output a set of clusters of those points. (i'm fine specifying # of clusters/cluster size/distance in advance to simplify) There are a few solutions on the web to do clustering, so it's a well known problem. I thought ...
Hi, I have a question regarding Clustering (session replication/failover) in tomcat 6 using BackupManager. Reason I chose BackupManager, is because it replicates the session to only one other server. I am going to run through the example below to try and explain my question. I have 6 nodes setup in a tomcat 6 cluster with BackupMana...
Hello Guys! I have been trying to install ejabberd server on Amazons EC2 instance. I am kinds a stuck at this step right now. I am following this guide: http://tdewolf.blogspot.com/2009/07/clustering-ejabberd-nodes-using-mnes... From the guide I have sucessfully completed the Set up First Node (on ejabberd1) part. But am stuck in part 4 ...
I have deployed a mysql cluster with 3 sql nodes. I create a NDB table in node1, then other nodes will create this table,too. I create a view in node1, then other nodes will not create this view. Now, my question is How to enable propagation of create view operation to other mysql cluster node? ...
While trying to debug a network problem, I've run into some difficulties understanding the output of some diagnostic tools. Context: distributed application over 7 nodes on a Linux cluster. 1GB ethernet, sustained data rate while on operation: 600Mbits per node (up+downstream). The symptom is a blocked TCP connection: sender blocks on a...
When I say coordinates I mean latitude and longitude coordinates of earth. I want to determine if a set of coordinates are within the same area (my cutoff is 200 miles). I've been googling "cluster alorithm" but I'm uncertain which would work best for me. Thanks ...
We are running thinking sphinx on a utility instance in our server cluster. It is rerunning the index every minute. But, if you make a change to a record, it disappears from search results until the index is updated (up to 1 minute). Is Thinking Sphinx only returning rows that have updated_at times that less than their last index? If...
I am developing a web application which is using php. It will use the mySQL database for storage. But The application may upgrade in future, so I would like to know is there any framework for me to reduce the pain of upgrading database structure. I know that there is a framework called cakePHP. And the application will deploy in more ser...
Hi guys, I want to do some experiment on SQL Server cluster to gain some experience on it, where should I start? I just have some basic concept of cluster and don't have any experience. Anyone can tell me some material that I can reference to? Great thanks. ...