heartbeat

What is the best way to implement a heartbeat in C++ to check for socket connectivity?

Hey gang. I have just written a client and server in C++ using sys/socket. I need to handle a situation where the client is still active but the server is down. One suggested way to do this is to use a heartbeat to periodically assert connectivity. And if there is none to try to reconnect every X seconds for Y period of time, and the...

How can I guarantee a "stay alive" heartbeat is sent?

We have an RMI client application written in Java which needs to send periodic "stay alive" messages to a server application. We have implemented this as a separate heartbeat thread, which sends the stay alive message to the server, then sleeps for 15 seconds using Thread.sleep(). The thread is set to be high priority: Thread heartbeat...

Polling a webpage periodically

I have a website where I need to poll a webpage in every minute or so. The page on the server will perform different task. I am trying to use Windows Scheduled Tasks, but that cannot be set to run in every minute. I know that there is cron jobs for this on Linux, but that is not available on Windows. Any ideas how to do this on Window...

Creating a "Heartbeat" or Windows-Service-Like functionality in Asp.Net

I've heard Jeff and Joel discuss on a podcast what they called a "Heartbeat" which essentially is creating something that acts similar to running a windows service in an website. I was hoping to get some more insight into how something like this would be implemented. Has anyone implemented something like this before and what did you use ...

setTimeOut() is not working with AJAX

In my application i want to send something to the server after some time. I have implemented it using AJAX. But it works for the first time but not doing it recursively. I have used setTimeOut() for doing that. var xmlHttp; var requestURL = 'http://localhost:1092/ClassicAJAXDemo/UpdateHeartbeat.aspx?name='; function show_da...

What are your opinions of DRBD/Heartbeat for replication and failover for the Firebird RDBMS?

I am researching the possibility of using Firebird for a project. However, one potential problem is replication and failover, or rather, lack of a (subjective) "good" solution. There are several potential solutions listed in the Firebird FAQ but they are either 1) Windows-centric; 2) horribly outdated; 3) commerical; or 4) not full-f...

detecting heartbeat peakpower using iphone sdk?

Hello all, i want to detect heart rate using iphone sdk does someone knows any method for calculating heartbeat rate? ...

How can I check if SQL server is alive?

I have a method to check and make sure my SQL server is online, which I use in some connection sensitive parts of my code. Although it works fine, I notice it takes upto 20ms to run, and I was wondering if anyone knows of a better way of checking SQL server to ensure its up and kicking. Here is my existing code. [System.Diagnostics.Co...

Do i have to maintain heart beating when using tcp?

one of the our distributed apps are using heart beat to detect the peer's disconnection(e.g. LAN line broken, etc) . is the heart beating necessary? ...

How would you change my Heartbeat process written in C#?

I'm looking at implementing a "Heartbeat" process to do a lot of repeated cleanup tasks throughout the day. This seemed like a good chance to use the Command pattern, so I have an interface that looks like: public interface ICommand { void Execute(); bool IsReady(); } I've then created several tasks that I want...

Customize WebLogic's heartbeat message

Hello, guys! I'm currently developing a system to ensure high performance, availability and scalability; fail-over and crash recovery on a WebLogic integration scenario. Does anybody know if it is possible to customize WebLogic's native heartbeat messages, to add some additional information such as current CPU usage and/or network load...

Linux HA / cluster: what are the differences between Pacemaker, Heartbeat, Corosync, wackamole?

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...

issues when Heartbeat starts in linux

I am using heartbeat3.0.3. when i am starting a heartbeat i am getting like this Starting High-Availability services: *** glibc detected *** heartbeat: free(): invalid pointer: 0x0810e428 *** ======= Backtrace: ========= /lib/tls/i686/cmov/libc.so.6[0xb7da7b25] /lib/tls/i686/cmov/libc.so.6(cfree+0x90)[0xb7dab590] heartbeat[0x805af61] h...

Getting heartbeat to fallover when apache service fails

I've currently got heartbeat set up nicely on ubuntu linux server so that if the heartbeat service is not detected (either because the server is down or just the heartbeat service is down) it fallsover to the secondary server as described in a blog post on my site. Having less than 10 reputation I can't post images, so here is a link in...

Multithreaded repeater in Python

I have small repeater Below that keeps ending, How can fix so more stable from crashes, and not stop running.... I would I add a heartbeat to the gui to see that its still running. In Wxpthon, my menu bar goes blank or white. def TimerSetup(): import threading, time invl = 300 def dothis(): try: ...

Good timeout for heartbeating proto using TCP - Java Sockets

Im implementing my own proto in Java, it will use a heartbeat over a TCP connection that I also use to transfer messages and files. For the client I am using blocking socket I/O. So here is how Im planning that will work... I will set the socket timeout for K seconds and make the heartbeat stay sending messages in an interval T, so that ...

How to query snmp trap through system floating IP?

I have written a snmp-agent, and it can run in system (rhel5). By querying oid from snmp client, it will get snmp trap. But my problem is: if there are two servers(one is stand-by system, one is active system),If I query snmp trap by floating IP, I will get no snmp trap. That is, I have to query by the true(active) IP, not floating IP....