Search Results

Search found 8495 results on 340 pages for 'high availability'.

Page 17/340 | < Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >

  • Powershell - remote folder availability while counting files

    - by ziklop
    I´m trying to make a Powershell script that reports if there´s a file older than x minutes on remote folder. I make this: $strfolder = 'folder1 ..................' $pocet = (Get-ChildItem \\server1\edi1\folder1\*.* ) | where-object {($_.LastWriteTime -lt (Get-Date).AddDays(-0).AddHours(-0).AddMinutes(-20))} | Measure-Object if($pocet.count -eq 0){Write-Host $strfolder "OK" -foreground Green} else {Write-Host $strfolder "ERROR" -foreground Red} But there´s one huge problem. The folder is often unavailable for me bacause of the high load and I found out when there is no connection it doesn´t report an error but continues with zero in $pocet.count. It means it reports everything is ok when the folder is unavailable. I was thinking about using if(Test-Path..) but what about it became unavailable just after passing Test-Path? Does anyone has a solution please? Thank you in advance

    Read the article

  • Which version management design methodology to be used in a Dependent System nodes?

    - by actiononmail
    This is my first question so please indicate if my question is too vague and not understandable. My question is more related to High Level Design. We have a system (specifically an ATCA Chassis) configured in a Star Topology, having Master Node (MN) and other sub-ordinate nodes(SN). All nodes are connected via Ethernet and shall run on Linux OS with other proprietary applications. I have to build a recovery Framework Design so that any software entity, whether its Linux, Ramdisk or application can be rollback to previous good versions if something bad happens. Thus I think of maintaining a State Version Matrix over MN, where each State(1,2....n) represents Good Kernel, Ramdisk and application versions for each SN. It may happen that one SN version can dependent on other SN's version. Please see following diagram:- So I am in dilemma whether to use Package Management Methodology used by Debian Distributions (Like Ubuntu) or GIT repository methodology; in order to do a Rollback to previous good versions on either one SN or on all the dependent SNs. The method should also be easier for upgrading SNs along with MNs. Some of the features which I am trying to achieve:- 1) Upgrade of even single software entity is achievable without hindering others. 2) Dependency checks must be done before applying rollback or upgrade on each of the SN 3) User Prompt should be given in case dependency fails.If User still go for rollback, all the SNs should get notification to rollback there own releases (if required). 4) The binaries should be distributed on SNs accordingly so that recovery process is faster; rather fetching every time from MN. 5) Release Patches from developer for bug fixes, feature enhancement can be applied on running system. 6) Each version can be easily tracked and distinguishable. Thanks

    Read the article

  • java distributed cache for low latency, high availability

    - by Shahbaz
    I've never used distributed caches/DHTs like memcached, jboss cache, ehcache, etc. I'm wondering which, if any, is appropriate for my use. First, I'm not doing web applications (as most of these project seem to be geared towards web apps). I write servers (Order Management Systems actually) for financial trading firms. The servers themselves are not too complicated. They need to receive information (market data, orders, executions, etc.) rout them to their destination while possibly transforming some of these messages. I am looking at these products to solve the following problems: * Safe repository of the state of the server. I'd rather build the logic of my application as a bunch of transformers (similar to Apache Camel) and store the state in a 'safe' place * This repository should be distributed: in case one of these data stores crashes, one or two more should be up and I should be able to switch to them seamlessly * This repository should be fast. Single digits milliseconds count here, in other words, systems which consume/process this data are automated systems, not humans clicking on links. This system needs to have high-throughput and low latency. By sending my data outside the process, I am necessarily slowing performance, but I am trying to balance absolute raw speed and absolute protection of data. * This repository should be safe. Similar to the point about several on-line backups, this system needs to write data to disk (potentially more than one disk). I'd really like to stop writing my own 'transaction servers.' Am I correct to be looking into projects such as jboss cache, ehcache, etc.? Thanks

    Read the article

  • Using Hidden Markov Model for designing AI mp3 player

    - by Casper Slynge
    Hey guys. Im working on an assignment, where I want to design an AI for a mp3 player. The AI must be trained and designed with the use of a HMM method. The mp3 player shall have the functionality of adapting to its user, by analyzing incoming biological sensor data, and from this data the mp3 player will choose a genre for the next song. Given in the assignment is 14 samples of data: One sample consist of Heart Rate, Respiration, Skin Conductivity, Activity and finally the output genre. Below is the 14 samples of data, just for you to get an impression of what im talking about. Sample HR RSP SC Activity Genre S1 Medium Low High Low Rock S2 High Low Medium High Rock S3 High High Medium Low Classic S4 High Medium Low Medium Classic S5 Medium Medium Low Low Classic S6 Medium Low High High Rock S7 Medium High Medium Low Classic S8 High Medium High Low Rock S9 High High Low Low Classic S10 Medium Medium Medium Low Classic S11 Medium Medium High High Rock S12 Low Medium Medium High Classic S13 Medium High Low Low Classic S14 High Low Medium High Rock My time of work regarding HMM is quite low, so my question to you is if I got the right angle on the assignment. I have three different states for each sensor: Low, Medium, High. Two observations/output symbols: Rock, Classic In my own opinion I see my start probabilities as the weightened factors for either a Low, Medium or High state in the Heart Rate. So the ideal solution for the AI is that it will learn these 14 sets of samples. And when a users sensor input is received, the AI will compare the combination of states for all four sensors, with the already memorized samples. If there exist a matching combination, the AI will choose the genre, and if not it will choose a genre according to the weightened transition probabilities, while simultaniously updating the transition probabilities with the new data. Is this a right approach to take, or am I missing something ? Is there another way to determine the output probability (read about Maximum likelihood estimation by EM, but dont understand the concept)? Best regards, Casper

    Read the article

  • Seven Worlds will collide…. High Availability BI is not such a Distant Sun.

    - by Testas
    Over the last 5 years I have observed Microsoft persevere with the notion of Self Service BI over a series of conferences as far back as SQLBits V in Newport. The release of SQL Server 2012, improvements in Excel and the integration with SharePoint 2010 is making this a reality. Business users are now empowered to create their own BI reports through a number of different technologies such as PowerPivot, PowerView and Report Builder. This opens up a whole new way of working; improving staff productivity, promoting efficient decision making and delivering timely business reports. There is, however; a serious question to answer. What happens should any of these applications become unavailable? More to the point, how would the business react should key business users be unable to fulfil reporting requests for key management meetings when they require it?  While the introduction of self-service BI will provide instant access to the creation of management information reports, it will also cause instant support calls should the access to the data become unavailable. These are questions that are often overlooked when a business evaluates the need for self-service BI. But as I have written in other blog posts, the thirst for information is unquenchable once the business users have access to the data. When they are unable to access the information, you will be the first to know about it and will be expected to have a resolution to the downtime as soon as possible. The world of self-service BI is pushing reporting and analytical databases to the tier 1 application level for some of Coeo’s customers. A level that is traditionally associated with mission critical OLTP environments. There is recognition that by making BI readily available to the business user, provisions also need to be made to ensure that the solution is highly available so that there is minimal disruption to the business. This is where High Availability BI infrastructures provide a solution. As there is a convergence of technologies to support a self-service BI culture, there is also a convergence of technologies that need to be understood in order to provide the high availability architecture required to support the self-service BI infrastructure. While you may not be the individual that implements these components, understanding the concepts behind these components will empower you to have meaningful discussions with the right people should you put this infrastructure in place. There are 7 worlds that you will have to understand to successfully implement a highly available BI infrastructure   1.       Server/Virtualised server hardware/software 2.       DNS 3.       Network Load Balancing 4.       Active Directory 5.       Kerberos 6.       SharePoint 7.       SQL Server I have found myself over the last 6 months reaching out to knowledge that I learnt years ago when I studied for the Windows 2000 and 2003 (MCSE) Microsoft Certified System Engineer. (To the point that I am resuming my studies for the Windows Server 2008 equivalent to be up to date with newer technologies) This knowledge has proved very useful in the numerous engagements I have undertaken since being at Coeo, particularly when dealing with High Availability Infrastructures. As a result of running my session at SQLBits X and SQL Saturday in Dublin, the feedback I have received has been that many individuals desire to understand more of the concepts behind the first 6 “worlds” in the list above. Over the coming weeks, a series of blog posts will be put on this site to help understand the key concepts of each area as it pertains to a High Availability BI Infrastructure. Each post will not provide exhaustive coverage of the topic. For example DNS can be a book in its own right when you consider that there are so many different configuration options with Forward Lookup, Reverse Lookups, AD Integrated Zones and DNA forwarders to name some examples. What I want to do is share the pertinent points as it pertains to the BI infrastructure that you build so that you are equipped with the knowledge to have the right discussion when planning this infrastructure. Next, we will focus on the server infrastructure that will be required to support the High Availability BI Infrastructure, from both a physical box and virtualised perspective. Thanks   Chris

    Read the article

  • Nginx php-fpm high cpu usage

    - by Piotr Kaluza
    I have a problem with a high traffic wordpress, super high CPU load under nginx php-fpm, I am caching with apc, and memcached, spent 2-3 days tweaking configs and looking for answers it seems to me that php-fpm takes up all the cpu available no matter how many max_children i set if i set 5 then the load is 20% each, if i set 20 then the load adds up till 90% i tried static and dynamic server is 2x3.0Ghz 6GB Ram SSD in raid 10 on ubuntu 12.04 x64 utpime: 17:27:51 up 2:19, 1 user, load average: 29.79, 28.08, 26.29 what can be the issue?

    Read the article

  • SQLS Timeouts - High Reads in Profiler

    - by lb01
    I've audited a SQLS2008 server with Profiler for one day.. the overhead didn't seem to trouble this new client my company has. They are using a legacy VB6 application as a front-end. They're experiencing timeouts once SQLS RAM usage is high. The server is currently running x64 sqls2008 on a VM with nearly 9 GB of RAM. SQL Server's 'max server memory option' is currently set to 6GB. I've put the results of the trace in a table and queried them using this query. SELECT TextData, ApplicationName, Reads FROM [TraceWednesday] WHERE textdata is not null and EventClass = 12 GROUP BY TextData, ApplicationName, Reads ORDER BY Reads DESC As I expected, some values are very high. Top Reads, in pages. 2504188 1965910 1445636 1252433 1239108 1210153 1088580 1072725 Am I correct in thinking that the top one (2504188 pages) is 20033504 KB, which then is roughly ~20'000 MB, 20GB? These queries are often executed and can take quite some time to run. Eventually RAM is used up because of the cache fattening, and timeouts occur once SQL cannot 'splash' pages in the buffer pool as much. Costs go up. Am I correct in my understanding? I've read that I should tune the associated T-SQL and create appropriate indices. Obviously cutting down the I/O would make SQL Server use less RAM. OR, maybe it might just slow down the process of chewing up the whole RAM. If a lot less pages are read, maybe it'll all run much better even when usage is high? (less time swapping, etc.) Currently, our only option is to restart SQL once a week when RAM usage is high, suddenly the timeouts disappear. SQL breathes again. I'm sure lots of DBAs have been in this situation.. I'm asking before I start digging out all of the bad T-SQL and put indices here and there, is there is something else I can do? Any advice except from what I know (not much yet..) Much appreciated. Leo.

    Read the article

  • SQLS Timeouts - High Reads in Profiler

    - by lb01
    Hi I've audited a SQLS2008 server with Profiler for one day.. the overhead didn't seem to trouble this new client my company has. They are using a legacy VB6 application as a front-end. They're experiencing timeouts once SQLS RAM usage is high. The server is currently running x64 sqls2008 on a VM with nearly 9 GB of RAM. SQL Server's 'max server memory option' is currently set to 6GB. I've put the results of the trace in a table and queried them using this query. SELECT TextData, ApplicationName, Reads FROM [TraceWednesday] WHERE textdata is not null and EventClass = 12 GROUP BY TextData, ApplicationName, Reads ORDER BY Reads DESC As I expected, some values are very high. Top Reads, in pages. 2504188 1965910 1445636 1252433 1239108 1210153 1088580 1072725 Am I correct in thinking that the top one (2504188 pages) is 20033504 KB, which then is roughly ~20'000 MB, 20GB? These queries are often executed and can take quite some time to run. Eventually RAM is used up because of the cache fattening, and timeouts occur once SQL cannot 'splash' pages in the buffer pool as much. Costs go up. Am I correct in my understanding? I've read that I should tune the associated T-SQL and create appropriate indices. Obviously cutting down the I/O would make SQL Server use less RAM. OR, maybe it might just slow down the process of chewing up the whole RAM. If a lot less pages are read, maybe it'll all run much better even when usage is high? (less time swapping, etc.) Currently, our only option is to restart SQL once a week when RAM usage is high, suddenly the timeouts disappear. SQL breathes again. I'm sure lots of DBAs have been in this situation.. I'm asking before I start digging out all of the bad T-SQL and put indices here and there, is there is something else I can do? Any advice except from what I know (not much yet..) Much appreciated. Leo.

    Read the article

  • Getting started with webserver clustering.

    - by Ernie
    I work for a small ISP, and we host about 250 domains and all the stuff that goes along with that: DNS, mail, spam filtering, and backups. Currently, we have separate DNS servers (two of them) and mail servers (outgoing mail is actually on the secondary DNS server, but was previously on its own server). In the past, this was done as an insurance measure. The last thing we need is for some doofus (usually yours truly) to hose a server, taking out DNS and mail right along with it, or for spammers to jam our incoming SMTP server, preventing outgoing mail from being sent too. In the past, this was a problem, and our servers were set up the way they are now to combat it. However, clustering solutions like Sun's Cobalt RAQ (in days of olde) and Virtualmin appear to cater to an all-in-one approach, then deal with failures through redundant servers. I have avoided this thus far, but we've been using Virtualmin on our web server for a while now, and I'd like to expand into using it for a high availability cluster. Our networking partner has recently built a datacenter that has eliminated all of our other bugaboos like network, cooling, and power issues, so now the only thing left to go wrong is me hosing a server, which happened earlier this month. One of the bigger reasons we've avoided going this route is because our hardware requirements aren't particularly high. One server easily handles all the sites we host (most of them are flat sites). Also, load-balancing routers tend to be expensive and complicated. All that I'm really expecting to do is building a two-node cluster for redundancy so that when I hose a server (however rare that might be), we're not out for 8-12 hours while I rebuild it. What I need to know is how to get started, and if I'm really in a position to bother with this kind of thing at all.

    Read the article

  • DNS failover in a two datacenter scenario

    - by wanson
    I'm trying to implement a low-cost solution for website high availability. I'm looking for the downsides of the following scenario: I have two servers with the same configuration, content, mysql replication (dual-master). They are in different datacenters - let's call them serverA and serverB. Users use serverA - serverB is more like a backup. Now, I want to use DNS failover, to switch users from serverA to serverB when serverA goes down. My idea is that I setup DNS servers (bind/powerdns) on serverA and serverB - let's call them ns1.website.com and ns2.website.com (assuming I own website.com). Then I configure my domain to use them as its nameservers. Both DNS servers will return serverA IP as my website's IP. If serverA goes down I can (either manually or automatically from serverB) change configuration of serverB's DNS, to return IP of serverB as website's IP. Of course the TTL will be low, as it's supposed to be in DNS failovers. I know that it may take some time to switch to serverB (DNS ttl, time to detect serverA failure, serverB DNS reconfiguration etc), and that some small part of users won't use serverB anyway. And I'm OK with that. But what are other downsides of such an approach? An alternative scenario is that ns1.website.com will return serverA IP as website's IP, and ns2.website.com will return serverB IP as website's IP. But AFAIK clients not always use primary nameserver and sometimes would use secondary one. So some small part of users would use serverB instead of serverA which is not quite what I'd like. Can you confirm that DNS clients behave like that and can you tell what percentage of clients would possibly use serverB instead of serverA (statistically)? This one also has the downside that when serverA goes back up, it will be automatically used as website's primary server, which is also a bad situation (cold cache, mysql replication could fail in the meantime etc). So I'm adding it only as a theoretical alternative. I was thinking about using some professional DNS failover companies but they charge for the number of DNS requests and the fees are very high (why?)

    Read the article

  • What database is easy to maintain and manage in a cluster?

    - by Sanoj
    I'm looking for a database (DBMS) that is easy to scale out. I would like to have high availability so I need a multi-master cluster, where the data is replicated to two or more physical computers. I would also like to be able to start with one node (no replication), and then scale out to more nodes as needed without a reinstallation or downtime. I would like to have a DBMS that are easy to maintain and manage. It should be easy to add nodes, remove nodes, take live backup and monitor the use of resources. It doesn't have to be a relational database system, so a NoSQL is okey. And I would like to have a free version so I can test it in small scale and compare it with alternatives. What alternatives do I have?

    Read the article

  • (simple) linux HA with vmware vsphere?

    - by derhelge
    I hope my upcoming question is specific enough, and you are able and willing to support :-) We have several openSUSE VMs in an ESX-Cluster (three ESX-Servers) with an attached iSCSI-SAN. All of those Linux VMs are "single point of failure"-configured, which means in the case of a Web-Server: LAMP, storage, etc. everything on this machine. This was very simple and in case of a failure (in the last years: kernel panics or apache crashes) a simple reboot triggered by a script did it. But the problem is: How to upgrade/maintain the w(eb-)application or the underlying OS without downtime? This wasn't really managable and i did this in the early morning ;) How can i achieve a "simple" High-Availability Cluster now? I thought of: DRBD with heartbeat with 2 VMs. And for the storage a RDM (raw device mapped) LUN and change the read-write-permissions for both VMs. Is this a good idea? Anyone has a better solution?

    Read the article

  • SonicWall HA "gotchas"?

    - by Mark Henderson
    We're looking to move away from PFSense and CARP to a pair of SonicWall NSA 24001 configured in Active/Passive for High Availability. I've never dealt with SonicWall before, so is there anything I should know that their sales guy won't tell me? I'm aware that they had an issue with a lot of their devices shutting down connectivity because of a licensing fault, and they have an overtly complex management GUI (on the older devices at least), but are there any other big "gotchas" that I need to be aware of before committing a not insubstantial amount of money towards these devices? 1If you're outside the US, the SonicWall global sites suck balls. Use the US site for all your product research, and then use your local site when you're after local information.

    Read the article

  • Highly Available Web Application (LAMP)

    - by Anthony Rizzo
    I work for a small company who provides a web application for thousands of users. Earlier this year they had one server hosted one company. We recently acquired another server in a different location with the hopes of one day making this a redundant failover machine. I understand what to do with the mysql replication, I plan on using a master-master replication setup, and rsync to sync the scripts and files, however I am at a stand still about how to configure the fail-over. Ideally I would like the two machines to accept requests, like a round robin dns, however if one machine goes down I do not want requests to go that machine. All of the solutions I am come across assumes high availability of servers in the same location, these servers are in two completely different locations with different public ip address. Any help would be great. Thanks

    Read the article

  • What happens if an OpenStack cloud controller dies?

    - by magu
    I've been reading up on OpenStack and how we can re-create an EC2/S3-style cloud for our internal development and I'm having a hard time finding information on how the OpenStack cloud controller provides redundancy of the cloud management services. I know I can setup multiple Swift and Nova nodes, but not a single document/article/howto/wiki contains information on: a) what happens if the cloud controller node dies; and b) how to setup redundant cloud controllers. It seems to me that, although it is massively scalable, there is a big single-point-of-failure built into OpenStack. Can anyone with more experience on OpenStack please shed some light as to how it all works in regards to high-availability?

    Read the article

  • How to configure HA iSCSI for Solaris 10

    - by Noah
    BACKGROUND: We have a StarWind NAS that we are currently using for High Availability storage with our Windows network. Starwind has mirrored drives and multiple ip paths, that the Windows Server combines into one HA disk store. QUESTION: How do I accomplish the same thing under Solaris 10? I've looked at ZFS but to document seems to indicate that ZFS wants to do its own raid/mirroring. I can also attach via iSCSI from Solaris and am presented with both drives being served by the Starwind NS. So, how do I configure solaris so that disk M1 and M2 are considered as a single fault tolerant drive?

    Read the article

  • How to setup a simple Ubuntu Server Tomcat cluster on VirtualBox for testing?

    - by Alex Pakka
    I am looking for a step by step instructions to setup at leat two (and later more) simple Ubuntu Virtual Core 12.10 Server VMs on Oracle VirtualBox under Windows 7 64bit. The test setup would be: Apache HTTP server on the Windows host acting as a Load Balancer. The result will be that going to http://localhost:8080 would balance between two nodes and prove session replication. Two lean, small footprint Ubuntu Server guest nodes with Java 7 and Tomcat 7. The intention is to help everyone doing High Availability / Load Balancing development and testing to create a reasonable environment on the local workstation or mainstream notebook in as little time as possible.

    Read the article

  • Can I use Veritias Storage Manager to provide HA storage using server-local storage?

    - by Paul
    I have a need to provide an high-availability ftp/http file repository. Upload will happne to one server, but the uploaded file must be immediately visisble on all other servers I can handle the failover of the servers themeselves using load balancers. But in the event of failure of one server, the other servers must see the same contents of the repository. Normally, I'd use a SAN for this, but in this case the data centre standards do not allow SAN/external storage - all storage will be local to the servers. Cam I use Veritas Storage Manager (or any other product) to manage mirroring hte contents between servers in this way? Or does that require a SAN? I couldn't tell either way from a quick look at the data sheets etc.

    Read the article

  • High CPU usage by 'svchost.exe' and 'coreServiceShell.exe'

    - by kush.impetus
    I am having a laptop running on Windows 7 Ultimate 32-bit. Since past few days, my laptop is facing a serious problem. Whenever I connect to Internet, either svchost.exe or coreServiceShell.exe or both hog the CPU. The coreServiceShell.exe consumes a lot of RAM also. Going into the details, I found that high CPU usage of svchost.exe is caused by Network Location Awareness service. And the high CPU usage of coreServiceShell.exe is caused by Trend Micro Titanium Internet Security 2012. That kind'a makes me think that Trend Micro may be the root of the problem. After further testing, I found that if I use IE or Firefox to browse the Internet, immediately after connecting to Internet, things are normal. See and But if I use Google Chrome, the coreServiceShell.exe hogs both CPU and RAM. At this point, if I disconnect the Internet, the CPU and RAM usage by coreServiceShell.exe continues to be high till I close the Chrome. Also, when I close the Chrome, while Internet is connected, svchost.exe continues to hog CPU but coreServiceShell.exe leaves the race. That makes think that Chrome is the root of the problem, but again, tracing coreServiceShell.exe takes me back to Trend Micro Internet Security. Stopping the Protection by the Trend Micro Internet Security doesn't help either (I am not able to stop its services though). I have updated the Chrome, but no help. I just can't figure out who is the culprit. I can't do without the Google Chrome (of course, by not using it) because of its immensely useful and indispensable features both during browsing and development. Secondly, I can't uninstall the Trend Micro Internet security Suite since it still has few months before it expires and is proving me reliable protection. What could be the cause of the problem and what can I do to resolve this? Thanks in advance

    Read the article

  • High latency issue for web service call from amazon aws ec2 to local server

    - by SibzTer
    We have a legacy web application that is running in our data center on premises located in Houston. We have a developed a new .net 4 based web application in order to provide new features to customers. The new web application is hosted in amazon aws ec2 environment (N. Virginia region us-east-1b zone). In order to get seamlessly integrate with the legacy application the new web application makes web service calls to retrieve data. We are seeing an unusually high latency time in the order of 5+ seconds for these web service calls. The exact same web service call returns in less than a second on our local PCs (which makes sense given physical proximity to the actual server). The weird part is that we have developers in California who also have the same milliseconds response time. We are testing the web service response using third party tools such as SoapUI, Google Chrome extensions such as Advanced REST Client, Postman REST Client, etc. As if this wasnt weird enough, we have noticed the same low latency from certain other ec2 instances while testing which are in the same region and availability zone as well. If we experienced the high latency consistently from all the ec2 instances I could understand. But there is something else going on. Comparing the various stats and results between the low latency and high latency ec2 servers do not show any significant differences: ping (constant 40ms), tracert, winmtr, etc. We have instances that are in the VPC as well. So I tried both the public and private IP address of the web service host server and that didnt make a difference either for the above results. We need to resolve this latency issue as this is causing the resulting web pages to load very slowly (almost 15+ seconds which is simply unacceptable). The ec2 instances have Windows Server Datacenter 64 bit. Let me know if there is any other infor I can provide to help diagnose this.

    Read the article

  • apache2 + mod_fastcgi + suexec + php5.2 = unstable on high load

    I am hosting several (~30) different sites on one server with apache2+fastcgi+suexec+php5. Sites have different loads and different execution times of their scripts (some of them process request for 5-7 seconds, some <1sek). Sometimes when single site receives very high load (all php instances of this site are created and used) - whole apache server hangs. Apache (worker mpm) creates new processes up to the upper limit. It looks like it is starting to queue ALL new request for EVERY site, not only the one that has high load and quickly achieves process limits... restart of apache solves the problem... config: FastCgiConfig -singleThreshold 1 -multiThreshold 10 -listen-queue-depth 30 -maxProcesses 80 -maxClassProcesses 12 -idle-timeout 30 -pass-header HTTP_AUTHORIZATION -pass-header If-Modified-Since -pass-header If-None-Match (earlier have default -listen-queue-depth = 100, but it didn't change anything...) Any suggestions? Another question - how is implemented this listen queue? is it one queue for whole apache, or unique queue for every defined php apllication (suexec site)? I would like to achieve something like this: when one site receives high load and its queue is full - server bounces next request, but only for this one site.. Other sites should work properly...

    Read the article

  • High disk I/O activity in CentOS server

    - by triiim
    I have about 16 websites in a CentOS dedicated, and I am having some problems on high traffic hours, it seems to be a high disk I/O activity causing a general slowdown. I've installed atop and this is what I see on the bottom (the server has been restarted thats why the values are so low): *** system and process activity since boot *** PID RDDSK WRDSK WCANCL DSK CMD 1/18 2176 1.7G 7.3G 854.4M 39 mysqld 671 1248K 3.0G 0K 13 flush-8:0 566 0K 1.1G 0K 5 jbd2/sda2-8 2401 124.2M 529.1M 22408K 3 crond 2032 2.2G 502.0M 0K 12 nginx 2360 425.8M 115.3M 4188K 2 httpd flush-8:0 and jbd2/sda2-8 are the processes I see with iotop using 99% on the IO column, and they are the processes that write the most on the hdd (after mysql). From what I saw in google this could be caused by some ext4 related bug, the current kernel is: Linux srvr.com 2.6.32-71.29.1.el6.x86_64 #1 SMP Mon Jun 27 19:49:27 BST 2011 x86_64 x86_64 x86_64 GNU/Linux I asked the hosting support to update the kernel and they tried but they now say that the server wont boot with the new installed kernel and they had to go back to the previous, they are not helping very much. Does someone has any idea how could I solve the high disk usage caused by flush-8:0 and jbd2/sda2-8 processes?

    Read the article

  • Server high CPU load issue! ( Cpanel + CentOS 5)

    - by kenby
    Our server cpu load is high todays sometimes reaches to 560! .. We have the lastest Cpanel/whm and the kernel is update!while the load average is : Load Averages: 39.05 75.01 45.33 the apache log is: Current Time: Sunday, 30-Jan-2011 01:50:13 EST Restart Time: Saturday, 29-Jan-2011 21:51:20 EST Parent Server Generation: 2 Server uptime: 3 hours 58 minutes 53 seconds Total accesses: 149493 - Total Traffic: 2.4 GB CPU Usage: u9.17 s10.66 cu42.82 cs0 - .437% CPU load 10.4 requests/sec - 174.6 kB/second - 16.7 kB/request 121 requests currently being processed, 42 idle workers W_WWW.W_..W.W_W_WCWW..W...W.WWW.WWWW.WW.C_W_.W.WW.WC..W.WW.WW .W.W.W...WWWW...WW.CC.C.._W.WC.WW_WW._W....W.WWW.W.WWW.W..W WW.....WW.W_WWWWW..WCRW..WWCW.WWW__.WWWWCW_W._._WW_W...W...W _W..W..WW.W...._W..._WW.W.WWW.._W.WWW.WWW....WW_.C...W._ Scoreboard Key: "_" Waiting for Connection, "S" Starting up, "R" Reading Request, "W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup, "C" Closing connection, "L" Logging, "G" Gracefully finishing, "I" Idle cleanup of worker, "." Open slot with no current process What cause this high cpu load while the apache cpu load is fine? the mysql process is also fine.. the cpu load is still high even if I stop mail-http-mysql services!

    Read the article

  • Avoiding DNS timeouts when a dns server fails

    - by user65124
    Hi there. We have a small datacenter with about a hundred hosts pointing to 3 internal dns servers (bind 9). Our problem comes when one of the internal dns servers becomes unavailable. At that point all the clients that point to that server start performing very slowly. The problem seems to be that the stock linux resolver doesn't really have the concept of "failing over" to a different dns server. You can adjust the timeout and number of retries it uses, (and set rotate so it will work through the list), but no matter what settings one uses our services perform much more slowly if a primary dns server becomes unavailable. At the moment this is one of the largest sources of service disruptions for us. My ideal answer would be something like "RTFM: tweak /etc/resolv.conf like this...", but if that's an option I haven't seen it. I was wondering how other folks handled this issue? I can see 3 possible types of solutions: Use linux-ha/Pacemaker and failover ips (so the dns IP VIPs are "always" available). Alas, we don't have a good fencing infrastructure, and without fencing pacemaker doesn't work very well (in my experience Pacemaker lowers availability without fencing). Run a local dns server on each node, and have resolv.conf point to localhost. This would work, but it would give us a lot more services to monitor and manage. Run a local cache on each node. Folks seem to consider nscd "broken", but dnrd seems to have the right feature set: it marks dns servers as up or down, and won't use 'down' dns servers. Any-casting seems to work only at the ip routing level, and depends on route updates for server failure. Multi-casting seemed like it would be a perfect answer, but bind does not support broadcasting or multi-casting, and the docs I could find seem to suggest that multicast dns is more aimed at service discovery and auto-configuration rather than regular dns resolving. Am I missing an obvious solution?

    Read the article

  • Avoiding DNS timeouts when a dns server fails

    - by Neil Katin
    We have a small datacenter with about a hundred hosts pointing to 3 internal dns servers (bind 9). Our problem comes when one of the internal dns servers becomes unavailable. At that point all the clients that point to that server start performing very slowly. The problem seems to be that the stock linux resolver doesn't really have the concept of "failing over" to a different dns server. You can adjust the timeout and number of retries it uses, (and set rotate so it will work through the list), but no matter what settings one uses our services perform much more slowly if a primary dns server becomes unavailable. At the moment this is one of the largest sources of service disruptions for us. My ideal answer would be something like "RTFM: tweak /etc/resolv.conf like this...", but if that's an option I haven't seen it. I was wondering how other folks handled this issue? I can see 3 possible types of solutions: Use linux-ha/Pacemaker and failover ips (so the dns IP VIPs are "always" available). Alas, we don't have a good fencing infrastructure, and without fencing pacemaker doesn't work very well (in my experience Pacemaker lowers availability without fencing). Run a local dns server on each node, and have resolv.conf point to localhost. This would work, but it would give us a lot more services to monitor and manage. Run a local cache on each node. Folks seem to consider nscd "broken", but dnrd seems to have the right feature set: it marks dns servers as up or down, and won't use 'down' dns servers. Any-casting seems to work only at the ip routing level, and depends on route updates for server failure. Multi-casting seemed like it would be a perfect answer, but bind does not support broadcasting or multi-casting, and the docs I could find seem to suggest that multicast dns is more aimed at service discovery and auto-configuration rather than regular dns resolving. Am I missing an obvious solution?

    Read the article

< Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >