Search Results

Search found 19923 results on 797 pages for 'instance variables'.

Page 121/797 | < Previous Page | 117 118 119 120 121 122 123 124 125 126 127 128  | Next Page >

  • why does and EBS volumes mounted in an Ubuntu 12.04 EC2 instance as /dev/sdh1 appear as /dev/xvdh1?

    - by Andres
    When mounting an EBS volume on ubuntu specified as /dev/sdh1 it actually mounts it at /dev/xvdh1. The aws console still thinks it's mounted at /dev/sdh1 so it took a while to realize that it was actually mounted, just in the wrong place I ran into this problem a long time ago using ubuntu on ec2. I just ran into it again https://forums.aws.amazon.com/post!reply.jspa?messageID=351382 and it seems like I'm not alone: https://forums.aws.amazon.com/thread.jspa?threadID=68957&tstart=0 I haven't found a good answer as to why this happens or how to fix it. Any ideas?

    Read the article

  • How to pass $_GET variables to a PHP script via the command line?

    - by George Edison
    I am trying to create a webserver that serves PHP scripts. Currently, it works as follows: The client requests /index.php?test=value The server invokes php index.php The server feeds the HTTP request headers as STDIN to the PHP process The server reads the output of php from STDOUT and returns it to the client All of this is working except that the parameters are not being passed to the PHP script because: var_dump($_GET); returns: array(0) { } How do $_GET parameters get passed to the PHP binary when it is invoked?

    Read the article

  • how can I manage user-dependent variables, that are valid on the whole domain ( Win Server 2003)

    - by Stephane R.
    Hello I am working on a system that needs a user-dependent variable, the user in on Windows XP and is connected to Windows Server 2003. I cannot save this variable in the registry of the local machine under HKCU, because the users are likely to exchange their machines. This variable must be accessible on the whole domain. Do you have any idea of implementing this ? Are there WMI features that may help me ?

    Read the article

  • How do I restore a Windows Server 2008 R2 bare metal backup to a Windows Server 2012 R2 Hyper-V instance?

    - by Michael J. Gray
    I have been trying to find a simple way to migrate a physical Windows Server 2008 R2 installation over to a virtual machine hosted on Windows Server 2012 R2 Datacenter Edition /w Hyper-V. I came across the bare metal backup feature on Windows Server 2008 R2 and assumed I would be able to easily back it up and simply restore it into a new virtual machine by booting the installation media and getting into the Windows recovery process. When I attempted this, Hyper-V got into a network based restore process, but I do not have a PXE server or anything like that and I would rather not set it up. I tried mounting the VHD produced in the bare metal backup, just to see if it would somehow work, but it of course did not and failed with an error related to an incorrect boot device. I checked the virtual machine's BIOS settings and everything looked fine. I did not expect this to work anyway, so I stopped working through this method any further. Is there a way to take my bare metal backup and restore it into a virtual machine without a PXE server or SCVMM? I am opening to using proprietary tools but since the last time I did this I used Norton Ghost, which is no longer supported, I figured I would try doing it with what is readily available.

    Read the article

  • How to reliably recieve message from AWS that my instance was rebooted / terminated / stopped?

    - by Andrew Smith
    I have Nagios, and I want it to stop monitoring instances when they are stopped from the console. The requirements are: The message passed from AWS is 100R% reliable, e.g. when Nagios is down, and the message cannot be delivered, it will be re-delivered promptly when Nagios is up The message will pass quickly There is no need to scan status of all instances via EC2 API all the time, but only once a while Many thanks!

    Read the article

  • How can I uninstall a clustered SQL instance if the cluster has been destroyed?

    - by Bob
    First time going through this scenario, and apparently I did it very wrong. On the DB servers I deleted the cluster group that held SQL and Reporting Services. I then destroyed the cluster. Then I tried to uninstall SQL. No dice. SQL still thinks its part of the non-existant cluster and will not let me uninstall it. I went into the Maintenance menu of the SQL setup and tried to Remove Node...nope. Unless I find a way out of this I will have to rebuild the OS if I can't get SQL off the box.

    Read the article

  • What is a preferred method for automatically configuring and setting up an Ubuntu instance?

    - by sutch
    I am tired of manually configuring instances of Ubuntu for testing web applications and for setting up workstations. I'm even more frustrated by the issues caused by inconsistent configurations. Is there a method (hopefully not too time consuming to learn and setup) that allows for automation of the setup and configuration of an Ubuntu server or workstation from an ISO. This is primarily for virtual machine instances, but it would be helpful to also create instances on hardware. I am specifically looking for a method to automate the installation of libraries (apt-get), configure services (such as Apache and MySQL), add 3rd party software (download, extract and build), and add libraries to scripting languages (for example, Ruby Gems or CPAN packages for Perl).

    Read the article

  • AWS autoscaling. Launch Config/Auto Scaling Group and VPC instance with two ifaces

    - by icalvete
    I want create an Launch Config/Auto Scaling Group to build instances inside an VPC with two subnets ("frontend" and "backend") I need that this instances have two ifaces. One in "frontend" subnet and one in "backend" subnet. I can't see how do that. It's no posible from AWS console and neither with aws cli. http://docs.aws.amazon.com/cli/latest/reference/autoscaling/create-launch-configuration.html http://docs.aws.amazon.com/cli/latest/reference/autoscaling/create-auto-scaling-group.html Launch Config don't say nothing about this. http://docs.aws.amazon.com/AutoScaling/latest/DeveloperGuide/create-lc-with-instanceID.html Ideas? Thanks!!!

    Read the article

  • Is it possible install one instance of Trac for multiple independent projects?

    - by grigy
    I want to set up an SVN/Trac environment for multiple projects, something like the GitHub. It will host multiple projects with multiple developers in each. For simplicity the developers can be independent from other projects. I want to setup this environment for every project automatically, from a registration page. What would be your recommendation? Particularly is it possible to do with Trac?

    Read the article

  • Unable to resize ec2 ebs root volume

    - by nathanjosiah
    I have followed many of the tutorials that pretty much all say the same thing which is basically: Stop the instance Detach the volume Create a snapshot of the volume Create a bigger volume from the snapshot Attach the new volume to the instance Start the instance back up Run resize2fs /dev/xxx However, step 7 is where the problems start happening. In any case running resize2fs always tells me that it is already xxxxx blocks big and does nothing, even with -f passed. So I start to continue with tutorials which all basically say the same thing and that is: Delete all partitons Recreate them back to what they were except with the bigger sizes Reboot the instance and run resize2fs (I have tried these steps both from the live instance and by attaching the volume to another instance and running the commands there) The main problem is that the instance won't start back up again and the system error log provided in the AWS console doesn't provide any errors. (it does however stop at the grub bootloader which to me indicates that it doesn't like the partitions(yes, the boot flag was toggled on the partition with no affect)) The other thing that happens regardless of what changes I make to the partitions is that the instance that the volume is attached to says that the partition has an invalid magic number and the super-block is corrupt. However, if I make no changes and reattach the volume, the instance runs without a problem. Can anybody shed some light on what I could be doing wrong? Edit On my new volume of 20GB with the 6GB image,df -h says: Filesystem Size Used Avail Use% Mounted on /dev/xvde1 5.8G 877M 4.7G 16% / tmpfs 836M 0 836M 0% /dev/shm And fdisk -l /dev/xvde says: Disk /dev/xvde: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x7d833f39 Device Boot Start End Blocks Id System /dev/xvde1 1 766 6144000 83 Linux Partition 1 does not end on cylinder boundary. /dev/xvde2 766 784 146432 82 Linux swap / Solaris Partition 2 does not end on cylinder boundary. Also, sudo resize2fs /dev/xvde1 says: resize2fs 1.41.12 (17-May-2010) The filesystem is already 1536000 blocks long. Nothing to do!

    Read the article

  • Can mod-rewrite be used to set environmental variables?

    - by VLostBoy
    Hi, I've got an existing simple rewrite rule like so: <Directory /path> RewriteEngine on RewriteBase / # if the requested resource does not exist RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d # route the uri to a front controller RewriteRule ^(.*)$ index.php/$1 [L] </Directory> This works fine, but I want to do one of either two things. On the basis of detecting the clients accept-language header, I want to either (i) Set the detected language as an environmental variable that the script can use or (ii)Rewrite the request so that the url begins with the language code (e.g. www.example.com/en/some/resource) In terms of implementing (i), I defined this rule: <Directory /path> RewriteEngine on RewriteBase / # if the requested resource does not exist RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d # if the users preferred language is supported... RewriteCond %{HTTP:Accept-Language} ^.*(de|es|fr|it|ja|ru|en).*$ [NC] # define an environmental variable PREFER_LANG RewriteRule ^(.*)$ - [env=PREFER_LANG:%1] # route the uri to a front controller RewriteRule ^(.*)$ index.php/$1 [L] </Directory> I've tried a few variations, but PREFER_LANG is not defined in $_SERVER nor retrievable by getenv. In terms of implementing (ii)... lets just say its messy. I'll post it if I can't get an answer to one. Can anyone advise me? Thanks!

    Read the article

  • Cloudwatch alarms from Amazon AWS EC2 instance are always in UT, how can I change the alarm time zone to Eastern?

    - by RightHandedMonkey
    I am running an Amazon linux AMI and the alarms that I've setup are coming in all showing UT (universal time). It is inconvenient reading these alarms and I'd like them setup to read in eastern time zone (or America/New_York). I've already set my /etc/localtime to point to - /usr/share/zoneinfo/America/New_York ln -s /usr/share/zoneinfo/America/New_York /etc/localtime But it is still sending alarms in the UT timezone. Does anyone have a solution to this?

    Read the article

  • Bootstrapped Ubuntu 12.04 EC2 instance. Where to find log?

    - by nocode
    So I bootstrapped a shell script to install and run a bunch of tasks. Looks like the it ran for the most part, but I added one part and that was formatting an extra EBS volume. Pretty straightforward: mkfs.ext4 /dev/xvdf mkdir –m 000 /vol01 echo “/dev/xvdf /vol01 auto noatime 0 0” | sudo tee –a /etc/fstab sudo mount /vol01 I was able to install MongoDB, NGINX and Forever. I selected to use /dev/xdvf in the AWS console and see it. The 3rd line is not in fstab either. I've searched through various logs in /var/log/ but I don't really see much indicating the execution of the bootstrap. Logs that I see and looked through: auth.log boot.log dmesg dpkg.log syslog udev

    Read the article

  • How to setup a virtual host in Ubuntu running on Amazon EC2 instance?

    - by Rade
    I have an app that's accessible via 1.2.3.4/myapp. The app is installed in /var/www/myapp. I've set up a subdomain(apps.mydomain.com) that points to 1.2.3.4. I want the server to point to var/www/myapp if I type apps.mydomain.com/myapp, how do I do that? I have experience creating virtual hosts(lots of them) locally but I'm lost because it's now in production and it's a little different. Here's my virtual host config: <VirtualHost *:80> ServerAdmin webmaster@localhost ServerName apps.mydomain.com/myapp DocumentRoot /var/www/myapp/public <Directory /> Options FollowSymLinks AllowOverride All </Directory> <Directory /var/www/> Options Indexes FollowSymLinks MultiViews AllowOverride All Order allow,deny allow from all </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride All Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog ${APACHE_LOG_DIR}/error.log # Possible values include: debug, info, notice, warn, error, crit, # alert, emerg. LogLevel warn CustomLog ${APACHE_LOG_DIR}/access.log combined </VirtualHost> Any idea why I still see the files instead of pointing me to the document root? Just in case someone might ask, the app is based on Laravel 4 framework. It's really bad right now because anyone can access the files from the browser.

    Read the article

  • mirror sql server 2008 to AWS instance from our datacenter?

    - by Alex
    We are currenlty running on hosted pos system locally and would like to mirror to AWS. We are new to AWS and would like to know the most cost effective way to do this? We have 2 DB and 2 web servers right now in one cabinet in CA. One tape drive, one firewall, one SNA. We are thinking to replicate our system in AWS (using sql server 2008) and just mirror both systems and use a witness server between them to keep the data in sync? The goal is, if CA datacenter goes down, AWS keeps running. User see no downtime. All data is synced. Is anyone doing something similar? Would this be practical to just use AWS in this fashion? Thanks

    Read the article

  • MySQL – Scalability on Amazon RDS: Scale out to multiple RDS instances

    - by Pinal Dave
    Today, I’d like to discuss getting better MySQL scalability on Amazon RDS. The question of the day: “What can you do when a MySQL database needs to scale write-intensive workloads beyond the capabilities of the largest available machine on Amazon RDS?” Let’s take a look. In a typical EC2/RDS set-up, users connect to app servers from their mobile devices and tablets, computers, browsers, etc.  Then app servers connect to an RDS instance (web/cloud services) and in some cases they might leverage some read-only replicas.   Figure 1. A typical RDS instance is a single-instance database, with read replicas.  This is not very good at handling high write-based throughput. As your application becomes more popular you can expect an increasing number of users, more transactions, and more accumulated data.  User interactions can become more challenging as the application adds more sophisticated capabilities. The result of all this positive activity: your MySQL database will inevitably begin to experience scalability pressures. What can you do? Broadly speaking, there are four options available to improve MySQL scalability on RDS. 1. Larger RDS Instances – If you’re not already using the maximum available RDS instance, you can always scale up – to larger hardware.  Bigger CPUs, more compute power, more memory et cetera. But the largest available RDS instance is still limited.  And they get expensive. “High-Memory Quadruple Extra Large DB Instance”: 68 GB of memory 26 ECUs (8 virtual cores with 3.25 ECUs each) 64-bit platform High I/O Capacity Provisioned IOPS Optimized: 1000Mbps 2. Provisioned IOPs – You can get provisioned IOPs and higher throughput on the I/O level. However, there is a hard limit with a maximum instance size and maximum number of provisioned IOPs you can buy from Amazon and you simply cannot scale beyond these hardware specifications. 3. Leverage Read Replicas – If your application permits, you can leverage read replicas to offload some reads from the master databases. But there are a limited number of replicas you can utilize and Amazon generally requires some modifications to your existing application. And read-replicas don’t help with write-intensive applications. 4. Multiple Database Instances – Amazon offers a fourth option: “You can implement partitioning,thereby spreading your data across multiple database Instances” (Link) However, Amazon does not offer any guidance or facilities to help you with this. “Multiple database instances” is not an RDS feature.  And Amazon doesn’t explain how to implement this idea. In fact, when asked, this is the response on an Amazon forum: Q: Is there any documents that describe the partition DB across multiple RDS? I need to use DB with more 1TB but exist a limitation during the create process, but I read in the any FAQ that you need to partition database, but I don’t find any documents that describe it. A: “DB partitioning/sharding is not an official feature of Amazon RDS or MySQL, but a technique to scale out database by using multiple database instances. The appropriate way to split data depends on the characteristics of the application or data set. Therefore, there is no concrete and specific guidance.” So now what? The answer is to scale out with ScaleBase. Amazon RDS with ScaleBase: What you get – MySQL Scalability! ScaleBase is specifically designed to scale out a single MySQL RDS instance into multiple MySQL instances. Critically, this is accomplished with no changes to your application code.  Your application continues to “see” one database.   ScaleBase does all the work of managing and enforcing an optimized data distribution policy to create multiple MySQL instances. With ScaleBase, data distribution, transactions, concurrency control, and two-phase commit are all 100% transparent and 100% ACID-compliant, so applications, services and tooling continue to interact with your distributed RDS as if it were a single MySQL instance. The result: now you can cost-effectively leverage multiple MySQL RDS instance to scale out write-intensive workloads to an unlimited number of users, transactions, and data. Amazon RDS with ScaleBase: What you keep – Everything! And how does this change your Amazon environment? 1. Keep your application, unchanged – There is no change your application development life-cycle at all.  You still use your existing development tools, frameworks and libraries.  Application quality assurance and testing cycles stay the same. And, critically, you stay with an ACID-compliant MySQL environment. 2. Keep your RDS value-added services – The value-added services that you rely on are all still available. Amazon will continue to handle database maintenance and updates for you. You can still leverage High Availability via Multi A-Z.  And, if it benefits youra application throughput, you can still use read replicas. 3. Keep your RDS administration – Finally the RDS monitoring and provisioning tools you rely on still work as they did before. With your one large MySQL instance, now split into multiple instances, you can actually use less expensive, smallersmaller available RDS hardware and continue to see better database performance. Conclusion Amazon RDS is a tremendous service, but it doesn’t offer solutions to scale beyond a single MySQL instance. Larger RDS instances get more expensive.  And when you max-out on the available hardware, you’re stuck.  Amazon recommends scaling out your single instance into multiple instances for transaction-intensive apps, but offers no services or guidance to help you. This is where ScaleBase comes in to save the day. It gives you a simple and effective way to create multiple MySQL RDS instances, while removing all the complexities typically caused by “DIY” sharding andwith no changes to your applications . With ScaleBase you continue to leverage the AWS/RDS ecosystem: commodity hardware and value added services like read replicas, multi A-Z, maintenance/updates and administration with monitoring tools and provisioning. SCALEBASE ON AMAZON If you’re curious to try ScaleBase on Amazon, it can be found here – Download NOW. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: MySQL, PostADay, SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

    Read the article

  • Amazon Web Services (AWS) Plug-in for Oracle Enterprise Manager

    - by Anand Akela
    v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif"; mso-bidi-font-family:"Times New Roman";} Contributed by Sunil Kunisetty and Daniel Chan Introduction and ArchitectureAs more and more enterprises deploy some of their non-critical workload on Amazon Web Services (AWS), it’s becoming critical to monitor those public AWS resources along side with their on-premise resources. Oracle recently announced Oracle Enterprise Manager Plug-in for Amazon Web Services (AWS) allows you to achieve that goal. The on-premise Oracle Enterprise Manager (EM12c) acts as a single tool to get a comprehensive view of your public AWS resources as well as your private cloud resources.  By deploying the plug-in within your Cloud Control environment, you gain the following management features: Monitor EBS, EC2 and RDS instances on Amazon Web Services Gather performance metrics and configuration details for AWS instances Raise alerts and violations based on thresholds set on monitoring Generate reports based on the gathered data Users of this Plug-in can leverage the rich Enterprise Manager features such as system promotion, incident generation based on thresholds, integration with 3rd party ticketing applications etc. AWS Monitoring via this Plug-in is enabled via Amazon CloudWatch API and the users of this Plug-in are responsible for supplying credentials for accessing AWS and the CloudWatch API. This Plug-in can only be deployed on an EM12C R2 platform and agent version should be at minimum 12c R2.Here is a pictorial view of the overall architecture: Amazon Elastic Block Store (EBS) Amazon Elastic Compute Cloud (EC2) Amazon Relational Database Service (RDS) Here are a few key features: Rich and exhaustive list of metrics. Metrics can be gathered from an Agent running outside AWS. Critical configuration information. Custom Home Pages with charts and AWS configuration information. Generate incidents based on thresholds set on monitoring data. Discovery and Monitoring AWS instances can be added to EM12C either via the EM12c User Interface (UI) or the EM12c Command Line Interface ( EMCLI)  by providing the AWS credentials (Secret Key and Access Key Id) as well as resource specific properties as target properties. Here is a quick mapping of target types and properties for each AWS resources AWS Resource Type Target Type Resource specific properties EBS Resource Amazon EBS Service CloudWatch base URI, EC2 Base URI, Period, Volume Id, Proxy Server and Port EC2 Resource Amazon EC2 Service CloudWatch base URI, EC2 Base URI, Period, Instance  Id, Proxy Server and Port RDS Resource Amazon RDS Service CloudWatch base URI, RDS Base URI, Period, Instance  Id, Proxy Server and Port Proxy server and port are optional and are only needed if the agent is within the firewall. Here is an emcli example to add an EC2 target. Please read the Installation and Readme guide for more details and step-by-step instructions to deploy  the plugin and adding the AWS the instances. ./emcli add_target \       -name="<target name>" \       -type="AmazonEC2Service" \       -host="<host>" \       -properties="ProxyHost=<proxy server>;ProxyPort=<proxy port>;EC2_BaseURI=http://ec2.<region>.amazonaws.com;BaseURI=http://monitoring.<region>.amazonaws.com;InstanceId=<EC2 instance Id>;Period=<data point periond>"  \     -subseparator=properties="=" ./emcli set_monitoring_credential \                 -set_name="AWSKeyCredentialSet"  \                 -target_name="<target name>"  \                 -target_type="AmazonEC2Service" \                 -cred_type="AWSKeyCredential"  \                 -attributes="AccessKeyId:<access key id>;SecretKey:<secret key>" Emcli utility is found under the ORACLE_HOME of EM12C install. Once the instance is discovered, the target will show up under the ‘All Targets’ list under “Amazon EC2 Service’. Once the instances are added, one can navigate to the custom homepages for these resource types. The custom home pages not only include critical metrics, but also vital configuration parameters and incidents raised for these instances.  By mapping the configuration parameters as instance properties, we can slice-and-dice and group various AWS instance by leveraging the EM12C Config search feature. The following configuration properties and metrics are collected for these Resource types. Resource Type Configuration Properties Metrics EBS Resource Volume Id, Volume Type, Device Name, Size, Availability Zone Response: Status Utilization: QueueLength, IdleTime Volume Statistics: ReadBrandwith, WriteBandwidth, ReadThroughput, WriteThroughput Operation Statistics: ReadSize, WriteSize, ReadLatency, WriteLatency EC2 Resource Instance ID, Owner Id, Root Device type, Instance Type. Availability Zone Response: Status CPU Utilization: CPU Utilization Disk I/O:  DiskReadBytes, DiskWriteBytes, DiskReadOps, DiskWriteOps, DiskReadRate, DiskWriteRate, DiskIOThroughput, DiskReadOpsRate, DiskWriteOpsRate, DiskOperationThroughput Network I/O : NetworkIn, NetworkOut, NetworkInRate, NetworkOutRate, NetworkThroughput RDS Resource Instance ID, Database Engine Name, Database Engine Version, Database Instance Class, Allocated Storage Size, Availability Zone Response: Status Disk I/O:  ReadIOPS, WriteIOPS, ReadLatency, WriteLatency, ReadThroughput, WriteThroughput DB Utilization:  BinLogDiskUsage, CPUUtilization, DatabaseConnections, FreeableMemory, ReplicaLag, SwapUsage Custom Home Pages As mentioned above, we have custom home pages for these target types that include basic configuration information,  last 24 hours availability, top metrics and the incidents generated. Here are few snapshots. EBS Instance Home Page: EC2 Instance Home Page: RDS Instance Home Page: Further Reading: 1)      AWS Plugin download 2)      Installation and  Read Me. 3)      Screenwatch on SlideShare 4)      Extensibility Programmer's Guide 5)      Amazon Web Services

    Read the article

  • Ninject & Entity Framework =(sometimes) "The ObjectContext instance has been disposed ..."

    - by n26
    I am using Ninject and ADO.Net Entity Framework in my Aps.Net (Mvc) website. I bind the ObjectContext to Ninject using the RequestScope: Bind<Entities>().ToSelf().InRequestScope().WithConstructorArgument("connectionString", _connectionString); In most cases this works perferct. But sometimes I got the following error: The ObjectContext instance has been disposed and can no longer be used for operations that require a connection. This error occurs at different positions while getting, updating, inserting or deleting data. In some cases this error occurs until I reset my webapp and sometimes it disappears after some requests. I am displeased that I have no more details. Because it seems that there is no pattern when and where this error occurs. Because the time and position is allways different :( Some hints or ideas?

    Read the article

  • Can the same CriteriaBuilder (JPA 2) instance be used to create multiple queries?

    - by pkainulainen
    This seems like a pretty simple question, but I have not managed to find a definitive answer yet. I have a DAO class, which is naturally querying the database by using criteria queries. So I would like to know if it is safe to use the same CriteriaBuilder implementation for the creation of different queries or do I have to create new CriteriaBuilder instance for each query. Following code example should illustrate what I would like to do: public class DAO() { CriteriaBuilder cb = null; public DAO() { cb = getEntityManager().getCriteriaBuilder(); } public List<String> getNames() { CriteriaQuery<String> nameSearch = cb.createQuery(String.class); ... } public List<Address> getAddresses(String name) { CriteriaQuery<Address> nameSearch = cb.createQuery(Address.class); ... } } Is it ok to do this?

    Read the article

  • "Object reference not set to an instance of an object": why can't .NET show more details?

    - by Simon Chadwick
    "Object reference not set to an instance of an object" This is probably one of the most common run-time errors in .NET. Although the System.Exception has a stack trace, why does the exception not also show the name of the object reference field, or at least its type? Over the course of a year I spend hours sifting through stack traces (often in code I did not write), hoping there is a line number from a ".pdb" file, then finding the line in the code, and even then it is often not obvious which reference on the line was null. Having the name of the reference field would be very convenient. If System.ArgumentNullException instances can show the name of the method parameter ("Value cannot be null. Parameter name: value"), then surely System.NullReferenceException instances could include the name of the null field (or its containing collection).

    Read the article

  • C#: Object reference not set to an instance of an object.

    - by Vinzcent
    Hey, I get the following error: Object reference not set to an instance of an object This is my C Sharp code: DataTable tableAcces = dsAcces.Tables["dsPrinterAcces"]; DataTable tableMDF = dsAcces.Tables["dsPrinterMDF"]; DataRow newrow = null; foreach(DataRow dr in tableAcces.Rows) { newrow = tableMDF.NewRow(); newrow["PRINTER_ID"] = dr["PRINTER_ID"]; newrow["MERK"] = dr["MERK"]; newrow["MODEL"] = dr["MODEL"]; newrow["LOKAAL_ID"] = dr["LOKAAL_ID"]; tableMDF.Rows.Add(newrow); } daMDF.Update(dsMDF, "dsPrinterMDF"); lblSucces.Text = "Gelukt. De tabel printers is overgezet."; } In this line, he throws the error: newrow = tableMDF.NewRow(); Thanks a lot, Vincent

    Read the article

< Previous Page | 117 118 119 120 121 122 123 124 125 126 127 128  | Next Page >