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• Using unixODBC to connect to Oracle server

  - by Paul

  I am trying to configure our web server (RHEL 5.4 x86) to connect to an Oracle database using unixODBC. I have installed unixODBC-2.2.11-7.1.1, which yum tells me is the latest version. I have also installed the Oracle InstantClient 11.2 and the Oracle InstantClient ODBC library. I have symlinked the all the .so files in /usr/lib/oracle/11.2/client/lib to /usr/lib. I have set $LD_LIBRARY_PATH to /usr/lib/, $ORACLE_HOME to /usr/lib/oracle and $TNS_ADMIN to the directory containing my (valid) Tnsnames.ora file. Here are the contents of my /etc/odbcinst.ini file: [Oracle] Description = Oracle ODBC Connection Driver = /usr/lib/libsqora.so.11.1 Setup = FileUsage = and my /etc/odbc.ini file: [Oracle] Application Attributes = T Attributes = W BatchAutocommitMode = IfAllSuccessful CloseCursor = F DisableDPM = F DisableMTS = T Driver = Oracle EXECSchemaOpt = EXECSyntax = T Failover = T FailoverDelay = 10 FailoverRetryCount = 10 FetchBufferSize = 64000 ForceWCHAR = F Lobs = T Longs = T MetadataIdDefault = F QueryTimeout = T ResultSets = T ServerName = //<host>:<port>/<db> SQLGetData extensions = F Translation DLL = Translation Option = 0 UserID = (ServerName has been edited...host, port, and db are actually there, and correct) When I run isql I get $ isql -v Oracle isql: symbol lookup error: /usr/lib/libsqora.so.11.1: undefined symbol: SQLGetPrivateProfileStringW And running dltest gives me $ dltest Oracle SQLConnect [dltest] ERROR dlopen: Oracle: cannot open shared object file: No such file or directory If anyone has any insights I would be grateful, I've been trying to get this to connect for about 5 hours now... I am going home for the night, but will gladly provide more details, if necessary, tomorrow morning, to anyone willing to help...

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• 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?

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• Site to Site VPN with Fault Tolerence

  - by Nordberg

  Hello, I have a situation where I require an IPSEC tunnel between two sites. Site 2 is a small branch office with basic (ADSL) connectivity and Site 1 is the "main" office with SDSL and ADSL for redundancy should the SDSL fail. From Site 1, all traffic bound for the 172.0.0.0 network will then be sent down another IPSEC tunnel to a supplier's Remote Server. See this page for the basic premise (this is a rough idea and things can be moved about etc...) I am considering specifying Cisco ASA devices as the firewalls for both sites for all connections. Would it be possible to employ something like HSRC to provide a backup at Site 1 should the SDSL go down? I suppose the key aims here are that Site 2 can somehow failover to initiate a VPN to the ASA behind the ADSL at Site 1. I will have a 21 subnet mask on all internet connections so can play with Class C routing if need be... If I'm barking up the wrong tree with HSRC, is there another way I can acheive this without massive expenditure on Barracuda routers et al? Many Thanks.

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• netlogon errors

  - by rorr

  I have two instances of mssql 2005 and am using CA XOSoft replication. The master is a failover cluster and the replica is a standalone server. They are all running Server 2003 sp2 x64. Same patch levels on all servers. This setup has worked great for several months until we recently restricted the RPC ports on both nodes of the master(5000 - 6000 using rpccfg.exe). We have to implement egress filtering, thus the limiting of the ports. We began receiving login errors for sql windows authentication and NETLOGON Event ID: 5719: This computer was not able to set up a secure session with a domain controller in domain due to the following: Not enough storage is available to process this command. This may lead to authentication problems. Make sure that this computer is connected to the network. If the problem persists, please contact your domain administrator. We also see group policies failing to update and cluster file shares go offline at the same time. The RPC ports were set back to default when we started seeing these problems and the servers rebooted, but the problems persist. The domain controllers are not showing any errors. Running dcdiag and netdiag shows everything is fine. We have noticed that the XOSoft service ws_rep.exe is using a lot of handles(8 - 9k), about the same number that sqlserver is using. As soon as xosoft replication is stopped the login errors cease and everything functions correctly. I have opened a ticket with CA for XOSoft, but I'm not sure that the problem is actually xosoft, but that it is the one bringing the problem to light. I'm looking for tips on debugging RPC problems. Specifically on limiting the ports and then reverting the changes.

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• BGP Multihomed/Multi-location best practice

  - by Tom O'Connor

  We're in the process of designing a new iteration of our network where we improve resilliency by adding a second datacentre. We'll be adding a second datacentre, with an identical configuration of servers as our primary location. To achieve network connectivity, we're looking into a couple of possible methods. See earlier questions http://serverfault.com/questions/86736/best-way-to-improve-resilience and http://serverfault.com/questions/101582/dns-round-robin-failover-and-load-balancing I'm pretty convinced that BGP is the right way to go about this, and this question is not about RRDNS. 1) If we have 2 locations, do we announce the same IP address block from both locations? 2) If we did this, but had a management ssh interface on x.x.x.50 from datacentre A, but it was on x.x.x.150 in datacentre B. What is the best practice mechanism for achieving this? Because if I were nearest to A, then all my traffic would go to x.50, but if i attempted to connect to x.150, I'd not be able to connect, because this address wouldn't be valid at A, but only at B. Is the best solution to announce 2 different netblocks, one at each location, facilitating the need for RRDNS, or to announce a single block, and run some form of VPN between the two sites for managment traffic?

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• Migrating Windows 2003 File Server Cluster to Windows 2008 R2 Standalone?

  - by Tatas

  We have a situation where we have an aging Windows 2003 File Server Cluster that we'd like to move to a standalone Windows Server 2008 R2 VM that resides in our Hyper-V R2 installation. We see no need to keep the Clustering as Hyper-V is now providing our Failover/Redundancy. Usually, in a standalone file server migration we migrate the data, preserving NTFS permissions and then export the sharing permissions from the registry and import them on the new server. This does not appear possible in this instance, as the 2003 cluster stores the sharing permissions quite differently. My question is, how would one perform this type of migration? Is it even possible? My current lead is the File Server Migration Toolkit, however I can find no information on the net about migrating from cluster to standalone, only the opposite. Please help. UPDATE: We ended up getting the data copied over (permissions intact), but had to recreate the shares manually by hand. It was a bit of a pain but it did in the end work out.

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• Azure load-balancing strategy

  - by growse

  I'm currently building out a small web deployment using VM instances on MS Azure. The main problem I'm facing at the moment is trying to figure out how to get the load-balancing to detect if a particular VM has failed and not route traffic to that VM. As far as I can tell, there are only only two load-balancing options: Have multiple VMs (web01, web02, web03 etc.) within the same 'cloud service' behind a single VIP, and configure the endpoints to be load balanced. Create multiple 'cloud services', put a single web VM in each and create a traffic manager service across all these services. It appears that (1) is extremely simplistic and doesn't attempt to do any host failure detection. (2) appears to be much more varied, but requires me to put all my webservers in their own individual cloud service. Traffic manager appears to be much more directed at a geographic failover scenario, where you have multiple cloud services across different regions. This approach also has the disadvantage in that my web servers won't be able to communicate with my databases on internal IP addresses, unlike scenario (1). What's the best approach here?

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• MySQL -- enable connection to remote server via local /tmp/mysql.sock

  - by Kevin

  Hey all, I run a shared hosting provider and we're looking to move to a High Availability (replicated across multiple datacenters) setup for our hosting. We have created a replicated MySQL setup with failover that works wonderfully, and we'd like to move all of our clients' databases to it. The only trouble is that we have many many customers, all of whom have configured their Wordpress, Drupal, etc. installations to connect to MySQL via a local socket, not to the address of the remove server. I would hate to have to go through manually and change the connection statement in all of our clients' sites. What I'd ideally love to see is a program that listens on /tmp/mysql.sock and forwards connections there to the remote server I specify. I've seen SQL Relay, but it seems to require that I hardcode all of the database names and usernames and passwords into its configuration file. This is not going to work for me because our users add new databases dynamically all of the time, and I'd rather not have to write code to updated SQLRelay's config file every time. Does anyone have an idea on how to do this? Alternatively, I'd accept idea on how to handle this at the PHP level. (i.e. redirect any attempted calls to mysql_connect() to use that hostname rather than localhost) Thanks, Kevin

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• Can you configure multiple KMS hosts in a primary / secondary relationship?

  - by Mark Hall

  We have two datacenters in our environment: primary and DR. I need to deploy a KMS service, and to be proactive, I would like to have a host in both datacenters. From what I have read, you can have up to 6 hosts without calling Microsoft, and it appears that what will happen is that a SRV record for each host will be placed in DNS. The client will query for those SRV records and randomly choose a host for the initial activation and will use that same server for all renewals. The server can be changed manually through a script and will automatically change if the initial server is unavailable when activating or renewing. My question is has anyone found a way to designate one server as the primary KMS host and designate the other as failover only? The reason I ask is that it is preferred that the client communicate with the primary datacenter during normal operations and only talk to the DR datacenter when needed because the bandwidth between the offices and the DR datacenter is limited compared to the primary. I am sure that this has been done before but I can not find it MSFT's documentation. Thanks, Mark

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• How to handle server failure in an n-tier architecture?

  - by andy

  Imagine I have an n-tier architecture in an auto-scaled cloud environment with say: a load balancer in a failover pair reverse proxy tier web app tier db tier Each tier needs to connect to the instances in the tier below. What are the standard ways of connecting tiers to make them resilient to failure of nodes in each tier? i.e. how does each tier get the IP addresses of each node in the tier below? For example if all reverse proxies should route traffic to all web app nodes, how could they be set up so that they don't send traffic to dead web app nodes, and so that when new web app nodes are brought online they can send traffic to it? I could run an agent that would update all the configs to all the nodes, but it seems inefficient. I could put an LB pair between each tier, so the tier above only needs to connect to the load balancers, but how do I handle the problem of the LBs dying? This just seems to shunt the problem of tier A needing to know the IPs of all nodes in tier B, to all nodes in tier A needing to know the IPs of all LBs between tiers A and B. For some applications, they can implement retry logic if they contact a node in the tier below that doesn't respond, but is there any way that some middleware could direct traffic to only live nodes in the following tier? If I was hosting on AWS I could use an ELB between tiers, but I want to know how I could achieve the same functionality myself. I've read (briefly) about heartbeat and keepalived - are these relevant here? What are the virtual IPs they talk about and how are they managed? Are there still single points of failure using them?

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• VMWare Newbie - looking for hardware recommendations and help :) [closed]

  - by Dan

  I am looking for some hardware recommendations on an upcoming virtualization project. We are a small company (80 users - 25 in site 1, 55 in site 2) currently using Windows Server 2003 - no VM servers yet. Our AD is setup where site 1 is the root domain and site 2 is a subdomain/subnet - connected by T1 and VPN for failover. The current DC's also server as file servers, print servers, AntiVirus servers. Email is in the cloud. Additionally then in site 1 we have 3 additional member servers - one running IBM Websphere for a customer specific app, one running Infor PowerLink (no real heavy load) and another that we use for Virtual Studio apps and also runs DirSync for Exchange Online. No heavy workloads on any of these machines really. We also have an AS400 box that we run ERP/CRM software on that site 2 connects to over the WAN link. In site 2 we also have a SQL machine that runs on Win2K server. Database files are not large less than 5 GB. Light to Medium workload on this machine. File servers in each site store less than 500 GB data and probably won't grow to more than 1TB in the next 5 years. I am looking to go to VMWare in both sites and virtualize all servers. What recommendations do you have for server, storage hardware? Is it safe to virtualize all of your DC's? Any help or advice would be greatly appreciated. Thanks.

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• How use DNS server to create simple HA (High availability) of my website?

  - by marc22

  Welcome, How can i use DNS server to create simple HA (High availability) of website ? For example if my web-server ( for better understanding i use internal IP in real it will be other hosting companies) 192.168.0.120 :80 (is offline) traffic go to 192.168.0.130 :80 You have right, i use bad word "hight avability" of course i was thinking about failover. Using few IP in A records is good for simple load-balancing. But not in case, if i want notice user about failure (for example display page, Oops something is wrong without our server, we working on it) against "can't establish connection". I was thinking about setting up something like this 2 DNS servers, one installed on www server Both have low TTL on my domain, set up 2 ns records first for DNS with my apache server second to other dns If user try connect he will get ip of www server using first dns, if that dns is offline (probably www server is also down) so it will try second NS record, what will point to another dns, that dns will point to "backup" page. That's what i would like to do. If You have other idea please share. Reverse proxy is not option, because IP of server can change, or i can use other country for backup.

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• 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?

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• How do I configure permissions for a cluster share using Powershell on 2008?

  - by Andrew J. Brehm

  I have a cluster resource of type "file share" but when I try to configure the "security" parameter I get the following error (excerpt): Set-ClusterParameter : Parameter 'security' does not exist on the cluster object Using cluster.exe I get a better result, namely the usual nothing when the command worked. But when I check in Failover Cluster Manager the permissions have not changed. In Server 2003 the cluster.exe method worked. Any ideas? Update: Entire command and error. PS C:\> $resource=get-clusterresource testshare PS C:\> $resource Name State Group ResourceType ---- ----- ----- ------------ testshare Offline Test File Share PS C:\> $resource|set-clusterparameter security "domain\account,grant,f" Set-ClusterParameter : Parameter 'security' does not exist on the cluster object 'testshare'. If you are trying to upda te an existing parameter, please make sure the parameter name is specified correctly. You can check for the current par ameters by passing the .NET object received from the appropriate Get-Cluster* cmdlet to "| Get-ClusterParameter". If yo u are trying to update a common property on the cluster object, you should set the property directly on the .NET object received by the appropriate Get-Cluster* cmdlet. You can check for the current common properties by passing the .NET o bject received from the appropriate Get-Cluster* cmdlet to "| fl *". If you are trying to create a new unknown paramete r, please use -Create with this Set-ClusterParameter cmdlet. At line:1 char:31 + $resource|set-clusterparameter <<<< security "domain\account,grant,f" + CategoryInfo : NotSpecified: (:) [Set-ClusterParameter], ClusterCmdletException + FullyQualifiedErrorId : Set-ClusterParameter,Microsoft.FailoverClusters.PowerShell.SetClusterParameterCommand

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• Creating basic, redundant gigE or IB storage network for Xen?

  - by StaringSkyward

  With only a modest budget, I want to move my 4 xen servers over to network storage -either NFS or iSCSI which will be determined based on how well it performs when we test it (we need good throughput and it must continue to work through link and switch failure tests). We may add another couple of xen servers at some point when this is done. I don't know much about the design and operation of storage networks, so would really appreciate some hints from those with experience. The budget is around $3,800 excluding the storage appliance. I am currently thinking these are my options to remain on budget: 1) Go for used infiniband hardware and aim for 10gb performance. 2) Stick with gig ethernet and buy some new switches (cisco or procurve) to create a storage-only ethernet LAN. Upgrade to 10gigE later but try to use hardware capable of it where possible to reduce upgrade costs. I have seen used, warrantied infiniband switches at reasonable prices (presumably because big companies are converging on 10gbit ethernet?) and the promise of cheap 10gb is attractive. I know nothing about IB, so here come the questions: Can I buy 2 x switches and have multiple HBAs in my xen and storage nodes to get redundancy and increased performance without complexity or expensive management software costs? If so, can you point me to some examples? Do NFS and iSCSI work just the same regardless? Is IB a sensible choice or could/should I use ethernet or FC on the same budget - I'm keen not to get boxed into a corner for future upgrades, however. For the storage I am likely to build a storage server using nexentastor with the intention that I can later add more disks, SSDs and add another server to provide a failover option at the storage level. An HP LeftHand starter SAN is also under consideration, too. Thanks in advance.

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• Router recommendation to virtualize 800 IPs

  - by delerious010

  I've recently been looking at getting some new load balancers for our environment as we are expecting to double our client base in the next 12 months. Currently we have 400 public IPS serving 800 clusters ( 2 clusters / IP due to ports ) on Coyote Point Balancers, and distributing connections to 3 web servers serving about 6GBytes outgoing, 2Gbytes in per day. If we double, this would be about 800 IPs, possibly 1600 clusters, and about 6 servers per cluster ( for a total of 9600 so called "real servers" using Barracuda's lingo ). Due to the amount of clusters, most solutions I've looked at ( Coyote, Barracuda, Loadbalancer.org ) seem to be unsure whether they'll be able to handle our planned growth, mostly due to health checks performed on the servers ... which makes total sense when you think of it. So the fine folk at loadbalancer.org recommended that we may be better off offload the 400-800 public IPs, which we require for SSL eCommerce solutions, over to a forward facing router. From that point on, the router could do some mangling to route EXT_IP:443 to INT_IP:INT_PORT which would then allow us to reduce the Load Balancer configuration to 1 or 2 clusters, thus resolving the health check problem. Does this idea make sense to yall ? Or would you have other recommendations to make ? Secondly, what router would you recommend for such an undertaking ? I'd be looking at something that has some form of failover mechanism built in. On a totally unrelated note, I've got to admit that I'm extremely pleased with the responses I got from loadbalancer.org. Their responses to my inquiries were surprisingly helpful ( i.e. I didn't feel as if I was taking to a sales guy trying to push something ). ( No I don't work for them, and sadly nor are they sending me free gear ).

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• Exchange 2010 Hub cannot deliver to Exchange 2007 Hub - "451 5.7.3 Cannot achieve Exchange Server authentication"

  - by Graeme Donaldson

  We have an existing Exchange 2007 server in Site A (exch07). I've installed an Exchange 2010 server in Site B (exch10). Both servers have the CAS, Mailbox and Hub roles. Messages sent via SMTP on exch10 which are destined for mailboxes on exch07 are queued with the "Last Error" reported in Queue Viewer as '451 4.4.0 Primary target IP address responded with: "451 5.7.3 Cannot achieve Exchange Server authentication." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts.' I've found that some people have resolved this by creating new Receive Connectors which are scoped specifically to apply to connections from the remote hub/s, but I have had no luck doing this. Specifically I created new receive connectors on both servers with the following settings: Remote IP = IP/s of remote server Authentication = "Transport Layer Security (TLS)" and "Exchange Server authentication" Permission Groups = "Exchange servers" and "Legacy Exchange Servers" This made no difference, I see the same error message. What am I missing? Update: We noticed that the Application log had this error message from MSExchangeTransportService: Microsoft Exchange could not find a certificate that contains the domain name exch07.domain.local in the personal store on the local computer. Therefore, it is unable to support the STARTTLS SMTP verb for the connector exch10 with a FQDN parameter of exch07.domain.local. If the connector's FQDN is not specified, the computer's FQDN is used. Verify the connector configuration and the installed certificates to make sure that there is a certificate with a domain name for that FQDN. If this certificate exists, run Enable-ExchangeCertificate -Services SMTP to make sure that the Microsoft Exchange Transport service has access to the certificate key. It turns out that the default self-signed certificate was no longer enabled for the SMTP service for some reason. After enabling the self-signed certificate for SMTP, we no longer get the error in the event logs, but delivery is still failing with the same error message. Update 2: I put a mailbox on exch10 and attempted to deliver a message via SMTP on exch07 and I get the same error.

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• Database mirroring login failure attempts on mirror server

  - by Chandan

  I have configured database mirroring between two servers at a distance 40 miles away from each other. Server specifications: SQL Server 2008,Standard Edition 64-bit This is same for principal,mirror and witness. The configuration is high-safety with automatic failover Initially we tested our .net application(web application) on both the principal and mirror and made sure that the login is not orpahned. Things run fine generally.But sometimes on the mirror server,I see login failed attempts: Login failed for user 'd0main\user'. Reason: Failed to open the explicitly specified database. [CLIENT: xx.xx.x.x] Message Error: 18456, Severity: 14, State: 38. This error appears 3-4 times a day but not more than that. My question to the experts is:If the principal is alive so why the application tries to connect to mirror.The default time-out for a .net webpage is 30 seconds,so is it possible that the application tries to connect principal and after 30 seconds even if principal is alive,it assumes that it is dead and thus tries to open a connection to mirror where it fails. Please help me with this problem.

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• Dynamic subdomain routing

  - by Nader

  Hi everyone, I asked this question over at stackoverflow, but got very few views: http://stackoverflow.com/questions/2284917/route-web-requests-to-different-servers-based-on-subdomain Perhaps it's more applicable to this crowd. Here it is again for convenience: I have a platform where a user can create a new website using a subdomain. There will be thousands of these, eg abc.mydomain.com, def.mydomain.com . Hopefully if we are successful hundreds of thousands. I need to be able to route these domains to a different IPs to point at a particular app server. I have this mapping in a database right now. What are the best practices and recommended technologies here? I see a couple options: Have DNS setup with a wildcard CNAME entry so that all requests go to a single IP where perhaps two machines using heartbeat (for failover) know how to look up the IP in the database and then do an http redirect to the appropriate app server. This seems clunky and slow to me. Run my own DNS server that can be programatically managed such that when a new site is created a DNS entry is added. We also move sites around to different app servers, so I would need to be able to update DNS entries in close to real time. Thoughts anyone? Thanks. Update2: I've setup external wildcard DNS pointing at an HAProxy web server whose job it is to route requests to backend servers. The mapping is stored in our internal PowerDNS server. Question now is how to get the HAProxy server (or another) to use the value of the internal DNS and not some config file or access list? – Update: Based on some suggestions below, it seems like reverse-proxy server(s) is the way to go. As I'll be rebalancing the domain-server mapping, these need to work instantly and the TTL on a DNS solution could be a problem. Any recommendations on software to use considering this domain-IP data is stored in a DB, and I'll need this to be performant?

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• Exchange 2010 DAG + VMWare HA = no support?

  - by Dan

  We currently have an Exchange 2003 clustered environment (two machine cluster) that we're looking to upgrade to 2010. We recently purchased a VMWare virtualization environment (three Dell R710's with an EMC NS-120 serving up NFS datastores - iSCSI is available) that we wish to use for this new environment. I'm seeing that Microsoft does not support Exchange 2010 DAGs with a virtualization high availability solution (see links below). I would like to utilize the DAG to ensure the data stays available if one host goes down, and HA to ensure that if the physical host goes down, the VM will come back up on the other available host. Does anybody know why MS does not support this? VMWare HA will only restart the VM if it is hung/down - I don't see any difference between this and restarting the physical box if someone pulled the power... Will we only run into issues with support if it has something to do with HA/DAG failover or will they see we have HA and tell us to put it on a physical box even if it has nothing to do with HA? If we disable HA for these VM's will that satisfy them on a support case? Has anybody set up an Exchange 2010 DAG on VMware with HA enabled? Will they have any issues with using an NFS datastore? We have much greater flexibility on the EMC with NFS vs iSCSI, so I would prefer to continue utilizing that. Thanks for any input! http://www.vmwareinfo.com/2010/01/verifying-microsoft-exchange-2010.html Take a look at the second image under "Not Supported" http://technet.microsoft.com/en-us/library/aa996719.aspx "Microsoft doesn't support combining Exchange high availability solutions (database availability groups (DAGs)) with hypervisor-based clustering, high availability, or migration solutions. DAGs are supported in hardware virtualization environments provided that the virtualization environment doesn't employ clustered root servers."

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• Firebox 1250e Core Failing?

  - by Noah

  We have 2 Firebox 1250e Core firewall boxes in our production environment, serving as an active and passive mode. A few months back, the active box was flashing a warning light, so our consultant removed it, and plugged it in to a test network. Everything appeared to be working fine, so he reloaded it into the production environment, and we didn't see any other issues. Fast forward to last week, and out network was constantly dropping connections over RDC, timing out, and performing as if there was a traffic issue. I turned off the production box and everything began to work fine immediately. At this point though, I'm not sure how to proceed. Should the box be completely replaced? Is there any recommended testing we could do to determine if there is a failure of some type with this device? Should we try upgrading the software on it? I know the environment isn't the issue, since the passive box (which is now the active one) is working fine. We'd like to have 2 in production though for safety failover purposes. I am not a network admin, but am hoping someone here might be able to provide some guidance.

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• Experiences in Upgrading from Exchange 2003 to Exchange 2010

  - by gWaldo

  I'm currently running Exchange 2003 SP2 Cluster on a Server 2003 AD Forest (in native 2003 mode), and we beginning to plan the upgrade to Server 2008 AD and Exchange 2010. We have two main sites, one middle-sized office, and a couple of smaller sites which have DCs (which may be RODCs after the upgrade). Currently all of our Exchange cluster is in my main site, but we are considering using the new datastore paradigm for load-balance/failover at the other large site, but this is not set in stone. Right now we are in the information-gathering and planning phases. I am looking for input of any gotchas experienced while performing either upgrade, but especially the Exchange upgrade. Gotchas? What surprised you? What wasn't documented? What said one thing but was misleading? (Confusing either in content or severity.) What is great or horrible about the new system? What worked well? What worked poorly? If you were to do it over again...? (I know that this isn't so much a question that can be definitively answered, but I'm happy to reward insight and useful resources (not the Microsoft documentation, but Blogposts are welcome) with upvotes.) UPDATE A couple items of note: -We are not currently using OWA (currently only the admins), but it may become more of a consideration with iOS devices. -We do have a small number of Blackberries in the environment (< 10%). -In addition to the standard Exchange connectors, we have a third-party connector for Captaris RightFax integration.

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• Can I format a Veritas cluster shared volume from windows?

  - by spaghettidba

  We have a Microsoft Failover Cluster with dynamic disks managed by Veritas Storage Foundation. Today the sysadmins added a new disk for SQL Server but the cluster size on the volume was wrong, so I issued a quick format to change it. The disk volume failed, the SQL Server group failed as well and the cluster became unresponsive. After some minutes I managed to fail over to a passive node. The SAN admins say it's my fault because I shouldn't have formatted the disk from the Windows format applet, but I should have used Veritas Enterprise Administrator instead. Can a format operation bring offline a whole cluster group this way? Relevant error messages: From the eventlog: The cluster resource host subsystem (RHS) stopped unexpectedly. An attempt will be made to restart it. This is usually due to a problem in a resource DLL. Please determine which resource DLL is causing the issue and report the problem to the resource vendor. From the cluster.log ERR [RCM] rcm::RcmResControl::DoResourceControl: ERROR_RESOURCE_CALL_TIMED_OUT(5910)' because of 'Control(STORAGE_GET_DISK_INFO_EX) to resource 'NameOfTheDiskGroup' timed out.' Veritas Documentation: Excerpt from Symantec's documentation: Note: Before manually creating the resource, you must format the cluster-shared volume with NTFS using the VEA GUI and mount it on the node where you are trying to create the resource. Does this mean the disk cannot be formatted from Windows? I don't read it that way. For the record, I formatted many disks using the Windows applet in the past and nothing bad happened.

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• Changing Corosync/Heartbeat pair's active node based on MySQL/Galera cluster state

  - by Hace

  Background I'm planning on building a High Availability "cluster" for our Zabbix instance by placing two physical servers in one server room and two in another server room. In each server room one of the physical servers will run Zabbix on RHEL and the other will run Zabbix's MySQL database, also on RHEL. I'd prefer synchronous replication for the MySQL nodes so I'm planning on using Galera in a master-slave configuration. The Zabbix instances on the two Zabbix servers would be controlled by Heartbeat/Corosync (although Red Hat Cluster Suite is also an option...) If the Zabbix server in Server Room A goes down, the one in Server Room B becomes active (and vice versa). Ditto for the MySQL servers/instances. If either of those cases happen, however, the connection between the Zabbix server and the MySQL server becomes significantly slower as ti has to travel over WAN. Question Is it possible to configure the Heartbeat/CoroSync pair to instruct the MySQL/Galera cluster to change the master node to switch to (if available) the one that's in the server room as the active Heartbeat/Corosync -node and (more challengingly) is it possible to do the same in the other direction, i.e have the Galera cluster change the active Heartbeat/CoroSync server to be in the same room as the active MySQL master server in case of a failover in over to avoid unnecessary WAN transfers between the application and its DB? Theories Most likely I can get CoroSync to run something that'd log in to one of the DB nodes to change the MySQL/Galera master but I don't know if it's really possible to do anything similar in the other direction in Galera. Is it possible to define a "service" in CoroSync/Heartbeat so that both the service and its MySQL service would migrate as one if possible. Using the DB server that's behind WAN should still be a better option to DB downtime. Am I just using too many tools to solve a problem that'd be far simpler with something else?

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• Windows 2008 R2 Servers Sending Arp Requests for IPs outside Subnet

  - by Kyle Brandt

  By running a packet capture on my my routers I see some of my servers sending ARP requests for IPs that exist outside of its network. For example if my network is: Network: 8.8.8.0/24 Gateway: 8.8.8.1 (MAC: 00:21:9b:aa:aa:aa) Example Server: 8.8.8.20 (MAC: 00:21:9b:bb:bb:bb) By running a capture on the interface that has 8.8.8.1 I see requests like: Sender Mac: 00:21:9b:bb:bb:bb Sender IP: 8.8.8.20 Target MAC: 00:21:9b:aa:aa:aa Target IP: 69.63.181.58 Anyone seen this behavior before? My understanding of ARP is that requests should only go out for IPs within the subnet... Am I confused in my understanding of ARP? If I am not confused, anyone seen this behavior? Also, these seem to happen in bursts and it doesn't happen when I do something like ping an IP outside of the network. Update: In response to Ian's questions. I am not running anything like Hyper-V. I have multiple interfaces but only one is active (Using BACS failover teaming). The subnet mask is 255.255.255.0 (Even if it were something different it wouldn't explain an IP like 69.63.181.58). When I run MS Network Monitor or wireshark I do not see these ARP requests. What happens is that on the router capturing I see a burst of about 10 requests for IPs outside of the network from the host machine. On the machine itself using wireshark or NetMon I see a flood of ARP responses for all the machines on the network. However, I don't see any requests in the capture asking for those responses. So it seems like maybe it is maybe refreshing the arp cache but including IPs that outside of the network. Also when it does this NetMon doesn't show the ARP requests?

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