Slow stateful failover for mission critical applications
I have two CSS running vip redundancy,ip interface redundancy and redundant-index on a ASR active-backup model.
They are attached to separate 3750 which share vlan info via a port channel.
When the master fails, we see the VRIR negotiation and mastership of VIPs occurs normally but the script that we run to validate our services fails and the services go to a down state.
Since the gateway for the reals is a redundant VIP that stays alive always based on a DUMMY service, we believe this could be a mac address table update on the 3750.
Traffic back from the reals is still sent to the "old" port where the gateway used to live.
Failover takes several minutes and TCP sessions timeout defeting stateful failover.
Any ideas???
Thanks
MANUEL
VLAN1 STP State: Disabled
VLAN1: Root Max Age: 6 Root Hello Time: 1 Root Fwd Delay: 4
Designated Root: 06-a4-00-11-93-90-61-78
Bridge ID: 06-a4-00-11-93-90-61-78
Root Port Desg
Port State Designated Bridge Designated Root Cost Cost Port
VLAN11 STP State: Disabled
VLAN11: Root Max Age: 6 Root Hello Time: 1 Root Fwd Delay: 4
Designated Root: 06-a4-00-11-93-90-61-79
Bridge ID: 06-a4-00-11-93-90-61-79
Root Port Desg
Port State Designated Bridge Designated Root Cost Cost Port
e1 Fwd 06-a4-00-11-93-90-61-79 06-a4-00-11-93-90-61-79 0 19 8001
VLAN211 STP State: Disabled
VLAN211: Root Max Age: 6 Root Hello Time: 1 Root Fwd Delay: 4
Designated Root: 06-a4-00-11-93-90-61-7a
Bridge ID: 06-a4-00-11-93-90-61-7a
Root Port Desg
Port State Designated Bridge Designated Root Cost Cost Port
VLAN222 STP State: Disabled
VLAN222: Root Max Age: 6 Root Hello Time: 1 Root Fwd Delay: 4
Designated Root: 06-a4-00-11-93-90-61-7b
Bridge ID: 06-a4-00-11-93-90-61-7b
Root Port Desg
Port State Designated Bridge Designated Root Cost Cost Port
e3 Fwd 06-a4-00-11-93-90-61-7b 06-a4-00-11-93-90-61-7b 0 19 8003
Similar Messages
-
Could I use EJB in mission-critical task,like telecom realtime billing?
We will begin a project about telecom billing.The key point of the project is the realtime billing,which is must be processed with high speed and efficiency.We have a plan to use Tuxedo on which to run some services coded by c lanaguage.Other management facilities and interfaces with other system could be built by java(EJB).
Now ,I am wonder why couldn't we using EJB in billing task ? Is there any success story about using EJB model to build mission-citical system? or is EJB good for that?
thanksJoy Wind,
AFAIK, The answer is NO. Java itself is not "currently" suitable for real time applications.
However, there is a community process going on at http://www.rtj.org/.
There is also a reference implementation available which you can check out.
http://www.timesys.com/prodserv/java/index.cfm
I guess you can use it for proto-types and demos. However, if you want to use it in some mission critical application then you have to wait till it becomes a part of standard java.
hope this helps.
regards,
Abhishek. -
What could be the possible reason for a deployed application to run slow after the target pc comes out of standby mode? PC running XP and using the USB to communicate with the DAQ and driver boards. Application generated with 2010.
ThanksHello,
Usually default property is checked
system property -> devices ->usb root -> power management -> allow system to switch off device
Hope this help
Regards
Tinnitus
CLAD / Labview 2011, Win Xp
Mission d'une semaine- à plusieurs mois laissez moi un MP...
RP et Midi-pyrénées .Km+++ si possibilité de télétravail
Kudos always accepted / Les petits clicks jaunes sont toujours appréciés
Don't forget to valid a good answer / pensez à valider une réponse correcte -
I haven't shut it down in over a month. I shut it down yesterday for over 12 hours yet upon starting up again the slowness persists. Removed Google chrome application the speed arose slightly any tips? I contacted a support member but unfortunately my warranty has run out, he suggested that may be a result of putting the mac into sleep constantly, and not shutting down and that there may be files i can clear to remedy the issue. Any suggestions would be greatly appreciated,
Regards.First, back up all data immediately, as your boot drive might be failing.
There are a few other possible causes of generalized slow performance that you can rule out easily.
Reset the System Management Controller.
If you have many image or video files on the Desktop with preview icons, move them to another folder.
If applicable, uncheck all boxes in the iCloud preference pane.
Disconnect all non-essential wired peripherals and remove aftermarket expansion cards, if any.
Check your keychains in Keychain Access for excessively duplicated items.
Boot into Recovery mode, launch Disk Utility, and run Repair Disk.
Otherwise, take the steps below when you notice the problem.
Step 1
Launch the Activity Monitor application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Activity Monitor in the icon grid.
Select the CPU tab of the Activity Monitor window.
Select All Processes from the menu in the toolbar, if not already selected.
Click the heading of the % CPU column in the process table to sort the entries by CPU usage. You may have to click it twice to get the highest value at the top. What is it, and what is the process? Also post the values for % User, % System, and % Idle at the bottom of the window.
Select the System Memory tab. What values are shown in the bottom part of the window for Page outs and Swap used?
Next, select the Disk Activity tab. Post the approximate values shown for Reads in/sec and Writes out/sec (not Reads in and Writes out.)
Step 2
If you have more than one user account, you must be logged in as an administrator to carry out this step.
Launch the Console application in the same way you launched Activity Monitor. Make sure the title of the Console window is All Messages. If it isn't, select All Messages from the SYSTEM LOG QUERIES menu on the left. If you don't see that menu, select
View ▹ Show Log List
from the menu bar.
Select the 50 or so most recent entries in the log. Copy them to the Clipboard (command-C). Paste into a reply to this message (command-V). You're looking for entries at the end of the log, not at the beginning.
When posting a log extract, be selective. Don't post more than is requested.
Please do not indiscriminately dump thousands of lines from the log into this discussion.
Important: Some personal information, such as your name, may appear in the log. Anonymize before posting. That should be easy to do if your extract is not too long. -
PO for LAN failover and stateful failover link?
Hi.. We have 2 x ASA 5520s running ver 9.0. We plan to aggregate the 2 interfaces used for LAN failover and stateful failover into a lacp PO. So both the ASAs are connected to each other directly using these 2 interfaces and then we logically make it a one PO. We then assign the PO intface an ip. Is this supported?
You can use any unused interface (physical, redundant, or EtherChannel) as the failover link. (Source)
That said, It would be an uncommon implementation. I almost always see them on separate physical interfaces. -
CBAC Stateful Failover HA: ¿can it be used for three segments?
Hello team.
I need to protect three segments (inside, outside, DMZ) with two routers running CBAC and Stateful Failover High Availability.
I would like to know if the concept shown with two sample segments (inside, outside) in the documentation (http://www.cisco.com/en/US/prod/collateral/routers/ps5855/white_paper_c11_472858.html) can be extended for routers with three interfaces, each one attached to the segments I need to protect.
If this is a supported scenario, I would appreciate your pointing me to a sample configuration.
Thank you very much in advance.
Rogelio Alvez
ArgentinaRogelio,
Basicamente seria HSRP groups asi como el ASA usa el stateful link, el Router establece una asociacion con un IPC group que se configure por HSRP group:
Mira el siguiente link:
Step 6
ipc zone default
Example:
Router(config)# ipc zone default
Configures the interdevice communication protocol, Inter-Process Communication (IPC), and enters IPC zone configuration mode
Use this command to initiate the communication link between the active router and standby routers.
http://www.cisco.com/en/US/prod/collateral/routers/ps5855/white_paper_c11_472858.html
Si tienes alguna duda con mucho gusto.
Mike -
I have an iMac and a MacBook with Intel Core 2 Duo processors. I realize that this is within the stated requirements for Lion. However was wondering if by migrating to Lion this will result in too much demand on processor resources, thus a slower machine than using Snow Leopard?
Which iMac? Which Macbook? Both have had several model
itertations, even within the framework of a Core2Duo processor.
With that said, I have an early 2009 iMac 24", with 2.66 GHz
Core2Duo with 8 gig of RAM, and in my opinion, seems to be running
smoother and faster with Lion. -
Not a mission critical question:
This isnt a matte that is affecting my work, but it would be great to know why its happening (my supervisor cant explain it either)
This goes back to another thread, with regard to autoconfig.
Our system has a db tier with, oracle user ORADBDEV
On the tier we have two users:
applmgr APPCLDEV
oracle user APPDBDEV
Running autoconfig for APPCLDEV went fine.
Running for APPDBDEV did not. It completed, but some paths are still not correct.
For exmaple : echo $SCRIPT_TOP returns /oradbi3/oracle/devcomn/admin/scripts/DEV_**cl (it should be /DEV_**db)
Before running autoconfig I changed the uname -S to ***db. ALso changed it in smit hostname.
Its just annoying that now I have to remember that certain paths are not configured correctly. I was very careful in selecting the correct paths when running the adcfgclone.pl also.
Like I say, its not mission critical, just a pain in the rump.
Thanks.Running for APPDBDEV did not. It completed, but some paths are still not correct.
For exmaple : echo $SCRIPT_TOP returns /oradbi3/oracle/devcomn/admin/scripts/DEV_**cl (it should be /DEV_**db)Dan,
As APPDBDEV user is the owner of the database tier files, did you source the database env file (NOT the application env file) before running AutoConfig? -
We have received a note concerning stateful failover of the CSS series of products, where the CSS 110XX series doesn't support stateful failover, however the CSS 115XXX will. Here is the digest of the message;
On 3/6, Hosting Engineering and Operations issued an alert regarding the
CSS 11000 load balancer. This is an update to that alert.
Since that time, we have experienced another hardware failure of this
model device.
In response to this situation, the following has occured:
* Platform Engineeringis in the process of removing the CSS 11000
from the SOE. Itis on target to be removed in April.
* Operations hasre-inforced our escalation procedures with CISCO.
Qwest is to beissued a RMA immediately for this model.
* For newconfigurations including a CSS 11000, CCAR will require
an Individual CaseBasis (ICB) review and approval.
* For existing premiumand above customers whoes configurations
include a CSS 11000, HostingOperations is planning to replace them with
compatible device. These changes have been pre-approved by CCAR as long
as:
* the networktopology remains the same
* redundancy ispreserved
* CCAR gets notifiedof the replacement model so we can update our
records
* For existing basicand enhanced customers, we are drafting a
communique that alerts them tothe performance issues exerienced by Qwest
and providing suggestedalternative solutions.
In response to recent questions from the field.....
Stateful failover with redundant CSS 11000 Series Load Balancers:
The Bottom Line: Cisco CSS 11000 Series Load Balancers do not support
stateful
failover.
Will Cisco ever support this?: Yes, this is supported in the CSS 11500
Series,
known as Adaptive Session Redundancy (ASR)
I need this today, what can I do?: Choose an alternative product. The
F5 BIG-IP
load balancers support this functionality.
What is stateful failover anyhow?
Stateful failover is a technology that can maintain state information
between
the active load-balancer and the standby load-balancer. This state
information
can include: persistence mapping, telnet sessions, ftp sessions, tcp
session
state, etc...
Why should I be concerned?
Without state synchronization applications can break if there is a
failover from
the active to standby unit. FTP Sessions will be broken, Telnet
sessions will
be broken, and most importantly persistence state mapping will be lost.
What do I need to listen for to determine if stateful failover is
important?
1. E-commerce applications that require persistence mapping.
Persistence
mapping will keep a client session mapped to the same server for a
specified
amount of time. This is often important with shopping cart and other
e-commerce
applications.
2. Long-lived sessions. Whether they are planning to transfer large
files via
FTP or long-lived telnet sessions. Anytime a connection will be
required for a
long time and starting over is not an acceptable condition, then
stateful
failover is important.
Does this sound correct or is this a bunch of hot air?Yes. Stateful failover, or ASR as it is sometimes called, is available on the CSS 11500 and Catalyst 6500 Content Switch Modules (CSM) load balancing platforms. It is not supported on the CSS 11000 due to architectural limitations of that platform.
Stateful failover is available on these Cisco platforms today.
mikep -
Accelarate the Linux ATI Graphics card for java Swing application
Hi All,
I am using a ATI Radeon 9550 Graphic card in LFS (Linux from the scratch) environment. I want to enable the OpenGL-based pipeline for Java Swing application. I tried the -Dsun.java2d.opengl=true . But the Java swing application getting very slow.
How to overcome this problem?
Any one give the procedure to Accelerate ATI graphics card for Java Swing Application
How to verify Java swing use ATI graphics card ?
Thanks in advance..
Prabhu.SHi All,
I am using a ATI Radeon 9550 Graphic card in LFS (Linux from the scratch) environment. I want to enable the OpenGL-based pipeline for Java Swing application. I tried the -Dsun.java2d.opengl=true . But the Java swing application getting very slow.
How to overcome this problem?
Any one give the procedure to Accelerate ATI graphics card for Java Swing Application
How to verify Java swing use ATI graphics card ?
Thanks in advance..
Prabhu.S -
Network Load Balancing and failover for AFP Sharing
Dear all,
Somebody kindly teach me to use round robin DNS to perform the network load balancing, it's success but not the failover.
I have 4 xserve and want to do the load balancing and failover at the same time.
I have read the IP failover document and setup it successfully, but anyone know is it possible to do the IP failover for more than 2 server?
For example, 4 server serving the AFP service at the same time, maybe I have 1 more extra server to do the IP failover for thoese 4 servers.
As I know, IP failover require Firewire as the heartbeat detection. But one xserve only have 2 firewire ports. May I setting up the IP failover only by a ethernet port and an IP address? does it possible to detect and failover to any server after server down has been detected?
I believe load balancer maybe the best solution but its cost is too high.
Thanks any advance!
Karlleewell, u have 2 options here
software load balancing
request comes it foo.com -> ws7u2 hosting foo.com is configured to run as reverse proxy . this server sends any incoming requests to one of the four back end web server 7 handling your incoming request
hardware load balancing (this you need to invest)
request comes to hardware load balancer who responds for foo.com -> sends requests to four ws7 server hosting your application
you could try out how software load balancing works out for you before you invest in hardware load balancing
here is more instruction on configuring ws7 + reverse proxy (software load configuration)
- install ws7 on foo.com
- create a new configuration (choose port 80, disable java -
SPSiteCollection.Add in WCF service for FBA web application throws "user not found"
Hi,
I use SharePoint 2010 SP2. Programmatically I can create a FBA-based web application and now I want to add a new site collection ("/") subsequently. Everything is done in a WCF web service with its own application pool and web
application. In extracts my code looks like this:
const uint cLID = 1031;
const string cSiteWebTemplate = "BLANKINTERNETCONTAINER#0";
const string cAdminName = "i:0#.f|user|username";
const string cDisplayName = "username";
const string cSiteAdminEmail = "[email protected]";
SPWebApplication webApplication = SPWebApplication.Lookup(new Uri("https://www.someurl.com"));
using (SPSite newSite = webApplication.Sites.Add("/", "some title", "some site collection comment", cLID, cSiteWebTemplate, cAdminName, cDisplayName, cSiteAdminEmail, null, null, null, false))
I also have a Windows forms based application where the exactly same code (except the changes required for WCF services) runs smooth, no exceptions or errors.
Now every time the webApplication.Sites.Add-method is called inside the WCF service by any client I get the following exception (it is in German, English
translation in square brackets):
Microsoft.SharePoint.SPException: Der Benutzer kann nicht gefunden werden. [user cannot be found]
bei [at] Microsoft.SharePoint.Administration.SPSiteCollection.Add(SPContentDatabase database, SPSiteSubscription siteSubscription, String siteUrl, String title, String description, UInt32 nLCID, String webTemplate, String ownerLogin, String ownerName,
String ownerEmail, String secondaryContactLogin, String secondaryContactName, String secondaryContactEmail, String quotaTemplate, String sscRootWebUrl, Boolean useHostHeaderAsSiteName)
bei Microsoft.SharePoint.Administration.SPSiteCollection.Add(SPSiteSubscription siteSubscription, String siteUrl, String title, String description, UInt32 nLCID, String webTemplate, String ownerLogin, String ownerName, String ownerEmail, String secondaryContactLogin,
String secondaryContactName, String secondaryContactEmail, Boolean useHostHeaderAsSiteName)
bei Microsoft.SharePoint.Administration.SPSiteCollection.Add(String siteUrl, String title, String description, UInt32 nLCID, String webTemplate, String ownerLogin, String ownerName, String ownerEmail, String secondaryContactLogin, String secondaryContactName,
String secondaryContactEmail, Boolean useHostHeaderAsSiteName)
The process user is the same both for my Windows forms based application and my WCF service and I expect the code runs the same in both cases. I did not find any matching forum entry and I have no idea why a WCF service does not execute
the same way as a Windows forms application. Additionally, before applying SP2, I used an ASMX service with a similar code snippet and it also worked fine.
Can anyone please tell me why calling
webApplication.Sites.Add-method by a WCF service does not work? Is there anything I can do to make it work properly?The creation of a new web application using SharePoint API works in WCF service. I also lined out that...
SPWebApplication webApplication = SPWebApplication.Lookup(new Uri(https://www.someurl.com));
... works in WCF service. In return I really get the very web application that I requested. Also exactly the same code snippet is called by exactly the same user context both in WCF Service and Windows forms application. Only for Windows forms
application it does not throw the exception but in WCF Service it does. I had some WCF Service specialist colleague looking through the code and web.config and he stated it looks ok (unfortunately he does not have any experience with SharePoint).
If you state "It's not, then your WCF config is wrong" what do you think I need to add or change in web.config in order to make it work? BTW: I did not modify app.config in my Windows forms application, so I thought I do not need to modify my web.config. -
Re: Failover for SO's with context
Right, delivery of events is not guaranteed by Forte, even though
it is reasonable to rely on it in the case of two Forte servers on a LAN.
I would not go towards a solution for securing events delivery by
an acknowledgement mechanism (ack event or shared object notifier),
because of increased complexity and performance overhead.
On the other hand, a second simple security level can be provided by
enabling
your mirror/backup SO to be refreshed at will, by letting it get a
snapshot
of the current transient data to be mirrored, so you can :
- Start your partitions in any order (The mirror partition will first
task a
snapshot of the transient data, then will register for mirror events)
- Start and stop the mirror partition at will, without disrupting the
application
Then, if you do not trust events delivery, you can reinitialize your
mirror
periodically (say every 12 hours) to minimize the risks of losing
transient
data events.
Again, this solution is suited to low volumes of transient data.
I guess what Chad means by journaling is writing to a log file any
event (in a large sense) happening on data from its initial value. Then
if
you need to restore state, you re-play the events from the initial value.
This is a common solution in the banking area where you need to backup
values but also events on the values. I do not know how this can be
applied
to a generic mechanism with Forte, but it may be a good way to explore,
although probably more complex to implement with Forte than the
Backup SO/ Events pattern.
Hope this helps,
Vincent Figari
On Fri, 13 Feb 1998 10:39:03 -0600 Chad Stansbury
<[email protected]> writes:
Actually, since events (let alone distributed events) are not
'guaranteed delivery' in Forte, I would hesitate to use events
as a mechanism of mirroring your data - unless, of course, you
really don't require an industrial strength failover strategy.
This would also apply to asynchronous messaging (unless you
are careful to register for exception events (which again, aren't
guaranteed delivery) and have a mechanism to handle said
asynchronous exception events. I also know that Forte will retry
certain tasks when the service object it is sent to fails com-
pletely (like a NIL object exception), but don't know enough
about the internal workings of Forte to know under which conditions
this will occur.
I think that the most common method of a truly industrial-
strength, guaranteed-delivery mechanisms is via journaling...
which I know very little about, but is something that you should
be able to look up and study if that's what you require.
Again, if you don't care about the (admittedly small) chance
of an asynchronous call failing, then the suggestions that
Vincent has already made are good ones.
From: [email protected]
To: [email protected]
Cc: [email protected]
Sent: 2/13/98 9:13:17 AM
Subject: Re: Failover for SO's with context
Steven,
The pattern choice between external resource vs SO is dependent on the
type
of transient data you want to backup. Probably the external resource
is
better
suited to high volumes of data. We have implemented the 'Backup SO'
pattern because our transient data volumes are rather low (which I
guess
must
be the most common case for global, transient data).
Whatever the choice you do :
- Be sure to enforce encapsulation for updating the transient data, in
order to
guarantee that any modification to your transient data is duplicated
on
the backup
SO or the external resource
- About performances, the CPU cost is fairly low for your 'regular'
application if you
take care to :
* use asynchronous tasks to update the external resource
or
* use events to notify the backup SO
Now it is true that you will have a network overhead when using
events,
as your
backup SO shall be isolated in a remote partition on a remote
server.
That is one good argument to select the Backup SO pattern for low
volumes of
transient data.
If you choose the 'Backup SO' pattern, you will also have to be
careful
not sending
any distributed reference to your Backup SO but only clones.
Anyway, the backup SO pattern works fairly well for low volumes of
data,
but requires lots of testings and a good understanding of events and
communication
across partitions.
Hope this helps,
Vincent Figari
On Fri, 13 Feb 1998 09:24:57 +0100 Steven Arijs <[email protected]>
writes:
We're going to implement a failover scenario for our application.
Unfortunately, we also have to replicate the state of our failed
service
objects.
I've browsed the Forte site and found a TechNote concerning this
(TechNote 11074).
In this TechNote they talk about a service object that is responsible
for updating all backup service objects when needed.
It seems to me that when I implement that way, I will be creating a
lot
of overhead, i.e. I will be doing a lot of stuff several times.
What will be the effects on my performance ?
The way with the least performance loss would be to use an external
resource that is updated. But what if this external resource also
fails
Is there any one who has already implemented a failover scenario for a
service objects with state ?
Any help would be appreciated.
Steven Arijs
([email protected])
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866]
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866]Right, delivery of events is not guaranteed by Forte, even though
it is reasonable to rely on it in the case of two Forte servers on a LAN.
I would not go towards a solution for securing events delivery by
an acknowledgement mechanism (ack event or shared object notifier),
because of increased complexity and performance overhead.
On the other hand, a second simple security level can be provided by
enabling
your mirror/backup SO to be refreshed at will, by letting it get a
snapshot
of the current transient data to be mirrored, so you can :
- Start your partitions in any order (The mirror partition will first
task a
snapshot of the transient data, then will register for mirror events)
- Start and stop the mirror partition at will, without disrupting the
application
Then, if you do not trust events delivery, you can reinitialize your
mirror
periodically (say every 12 hours) to minimize the risks of losing
transient
data events.
Again, this solution is suited to low volumes of transient data.
I guess what Chad means by journaling is writing to a log file any
event (in a large sense) happening on data from its initial value. Then
if
you need to restore state, you re-play the events from the initial value.
This is a common solution in the banking area where you need to backup
values but also events on the values. I do not know how this can be
applied
to a generic mechanism with Forte, but it may be a good way to explore,
although probably more complex to implement with Forte than the
Backup SO/ Events pattern.
Hope this helps,
Vincent Figari
On Fri, 13 Feb 1998 10:39:03 -0600 Chad Stansbury
<[email protected]> writes:
Actually, since events (let alone distributed events) are not
'guaranteed delivery' in Forte, I would hesitate to use events
as a mechanism of mirroring your data - unless, of course, you
really don't require an industrial strength failover strategy.
This would also apply to asynchronous messaging (unless you
are careful to register for exception events (which again, aren't
guaranteed delivery) and have a mechanism to handle said
asynchronous exception events. I also know that Forte will retry
certain tasks when the service object it is sent to fails com-
pletely (like a NIL object exception), but don't know enough
about the internal workings of Forte to know under which conditions
this will occur.
I think that the most common method of a truly industrial-
strength, guaranteed-delivery mechanisms is via journaling...
which I know very little about, but is something that you should
be able to look up and study if that's what you require.
Again, if you don't care about the (admittedly small) chance
of an asynchronous call failing, then the suggestions that
Vincent has already made are good ones.
From: [email protected]
To: [email protected]
Cc: [email protected]
Sent: 2/13/98 9:13:17 AM
Subject: Re: Failover for SO's with context
Steven,
The pattern choice between external resource vs SO is dependent on the
type
of transient data you want to backup. Probably the external resource
is
better
suited to high volumes of data. We have implemented the 'Backup SO'
pattern because our transient data volumes are rather low (which I
guess
must
be the most common case for global, transient data).
Whatever the choice you do :
- Be sure to enforce encapsulation for updating the transient data, in
order to
guarantee that any modification to your transient data is duplicated
on
the backup
SO or the external resource
- About performances, the CPU cost is fairly low for your 'regular'
application if you
take care to :
* use asynchronous tasks to update the external resource
or
* use events to notify the backup SO
Now it is true that you will have a network overhead when using
events,
as your
backup SO shall be isolated in a remote partition on a remote
server.
That is one good argument to select the Backup SO pattern for low
volumes of
transient data.
If you choose the 'Backup SO' pattern, you will also have to be
careful
not sending
any distributed reference to your Backup SO but only clones.
Anyway, the backup SO pattern works fairly well for low volumes of
data,
but requires lots of testings and a good understanding of events and
communication
across partitions.
Hope this helps,
Vincent Figari
On Fri, 13 Feb 1998 09:24:57 +0100 Steven Arijs <[email protected]>
writes:
We're going to implement a failover scenario for our application.
Unfortunately, we also have to replicate the state of our failed
service
objects.
I've browsed the Forte site and found a TechNote concerning this
(TechNote 11074).
In this TechNote they talk about a service object that is responsible
for updating all backup service objects when needed.
It seems to me that when I implement that way, I will be creating a
lot
of overhead, i.e. I will be doing a lot of stuff several times.
What will be the effects on my performance ?
The way with the least performance loss would be to use an external
resource that is updated. But what if this external resource also
fails
Is there any one who has already implemented a failover scenario for a
service objects with state ?
Any help would be appreciated.
Steven Arijs
([email protected])
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866]
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866] -
Weblogic7/examples/clustering/ejb Automatic failover for idempotent methods ?
This one should be easy since it is from the examples folder of bea 7 about
clustering.
Ref : \bea7\weblogic007\samples\server\src\examples\cluster\ejb
I am referring to the cluster example provided with the weblogic server 7.0
on windows 2000.
I deployed Admin server and 2 managed server as described in document.
Everything works fine as shown by the example. I get load balancing and
failover both. Too Good.
Client.java is using the while loop to manage the failover. So on exception
it will go thru the loop again.
I understand from the documentation that the stateless session EJB will
provide the automatic failover for Idempotent stateless bean
Case Failover Idempotent : ( Automatic )
If methods are written in such a way that repeated calls to the same method
do not cause duplicate updates, the method is said to be "idempotent." For
idempotent methods, WebLogic Server provides the
stateless-bean-methods-are-idempotent deployment property. If you set this
property to "true" in weblogic-ejb-jar.xml, WebLogic Server assumes that the
method is idempotent and will provide failover services for the EJB method,
even if a failure occurs during a method call.
Now I made 2 changes to the code.
1 . I added as follows to the weblogic-ejb-jar.xml of teller stateless EJB
<stateless-clustering>
<stateless-bean-is-clusterable>true</stateless-bean-is-clusterable>
<stateless-bean-load-algorithm>random</stateless-bean-load-algorithm>
<stateless-bean-methods-are-idempotent>true</stateless-bean-methods-are-idem
potent>
</stateless-clustering>
So I should get the automatic failover .............
2. Also I added the break statement in the catch on line around 230 in
Client .java
catch (RemoteException re) {
System.out.println(" Error: " + re);
// Replace teller, in case that's the problem
teller = null;
invoke = false;
break;
So that the client program does not loop again and again.
Now I compile and restart all my three servers and redeploy application (
just to be sure )
I start my client and I get a automatic load balancing between the server
which makes me happy.
But Failover ....?
I kill one of the managed application server in cluster at any particular
test fail point.
I expect the exception to be taken care automatically by error/failover
handler in the home/remote stub
But the client program fails and terminates.
1. What is wrong with the code ?
2. Does the automatic failover with the indempotent methods also has to be
taken care by coding the similar while loop for stateless ejb ?
Your help will be appreciated ASAP.
Let me know if you need any thing more from my system. But I am sure this
will be very easy as it is from the sample code.........
Thanks
Sorry I meant to send this to the ejb newsgroup.
dan
dan benanav wrote:
> Do any vendors provide for clustering with automatic failover of entity
> beans? I know that WLS does not. How about Gemstone? If not is there
> a reason why it is not possible?
>
> It seems to me that EJB servers should be capable of automatic failover
> of entity beans.
>
> dan
-
CSS active-active stateful failover
Dear All,
May I confirm if CSS can do active-active stateful failover? If so, is it any restriction? and any Cisco URL I can refer to?
Thanks a lot.
makwhat do you call active-active ?
There different ways to achieve active-active.
What we can do is 1 vip active on 1 CSS-A and standby on CSS-B and a 2nd VIP active on CSS-B and standby on CSS-A.
But do you really need this ?
CSS can handle quite a huge amount of traffic so I never saw the need for active-active.
The failover can be statefull with CSS115xx not with CSS110xx or CSS118xx or CSS111xx.
Here is a sample config for one-armed mode but you can also have multiple vlans.
http://www.cisco.com/en/US/products/hw/contnetw/ps792/products_configuration_example09186a00802206a3.shtml
Regards,
Gilles
Maybe you are looking for
-
TS3074 I have Windows 8.1 and am having the "error 7" problem but I do not know how to fix it
I have an HP Windows 8.1 laptop that has been having problems, so I just got it serviced. They gave it back to me without most of my programs on there. I tried downloading itunes and thought that I had successfully, but I was wrong. Since then I have
-
Mail Adapter to Soap Adapter keeping the attachments - How?
Hi guys, I am working on a scenario where I should pull emails from an Exchange server and I should forward them (with their attachments) to a separate systems via a Web Service. So far I have been able to pull the emails using the Mail Adapter and I
-
Mini mac and a possible broken charger unit
In a discussion with a mate he asked if I ever had problems with charger units on my mac. He uses a mini mac in connection to an external harddrive. That external harddrive currently died during runtime. The mini mac itself was running fine till then
-
Hi Friends, I have setup a PM Orders which collect all the maintenance and running cost (internal service). I have assigned settlement Profile "Internal Order" with settlement rule "Mandatory for release". Now when I click settlement rule button in
-
How do i cancel Blackberry Music payments without the phone?
How do i cancel Blackberry Music payments without the phone? My daughters phone has gone but the payments continue to be taken. how can i cancel the payments when i don't have the phone?