Software :: Data Redundancy And Failover ?
Jan 3, 2010
I currently have 9 physical servers that I wanted to condense to 1 physical server with 7 VMs using Xen. The only issue that I have with doing this is that if the server happens to fail due to hardware problems, I am going to have a major issue. I wanted to set up a two node cluster so in the event of something happening to one of the servers, it will automatic failover to the next.
With so many ways to cluster servers, does anyone have any suggestions on the way to perform my needed task. The OS for Xen will be Red Hat and the VMs will have many versions of linux. Some of the VMs will have mysql, apache, dns, and postfix running.
View 1 Replies
ADVERTISEMENT
Feb 14, 2010
What is the current state of NFS failover (i.e. setting up two server with shared storage, with automatic failover if one fails?) I've seen a cookbook, but no details that would let me assess how well it works. There are lots of complex issues with data consistency, but the detailed information on that is years old. Our needs are fairly simple: 2 servers, a shared array, and I'm reasonably sure that we don't use locking. However we'd like failover to work reliably without loss of data.
View 3 Replies
View Related
Jun 16, 2011
I bought a brand new PC with 2 hard disk: a solid state 250gb and a 500gb sata drive. On the first one, I installed Ubuntu LTS 10.04.2.
My question is: how can I make the redundancy of the boot partition and / on the sata disk? I thought to clone the internal hard disk and then run a rsync before every shutdown. But the PC doesn't always boot from the ssd and change the boot sequence from the bios has no effect. I had also considered the idea of a raid 1 with mdadm, but it seems to worsen the performance.
View 6 Replies
View Related
Apr 17, 2010
Evening, had a switch outage today, what a PITA. ok, that's behind me, my next project is to have the least amount of single point of failures.
So the current scenario is the following; ISP -> linux firewall -> 3 network subnets.
1. load balanced network
2. public servers (ftp, etc.)
3. management network
I would like to change it to be more like; ISP -> switch, 2 patch cords to 2 seperate firewalls (right now using a basic linux box with iptables, works great), might go the endian or other route with failover. But, each server has a public IP and private 192.x ip, most server have 2 adapters 2 interfaces each, so I do have 4 ports already. I would like to send 1nic with public/private to switch1, the other to switch 2 but either keep them down, or better the same IP. So I guess, is this possible? I would say the word bonding, not sure if it can be used in this term. The webserver are running Ubuntu 9.10 64bit, DB's etc are mostly CentOS 5.4 box's.
We have all dell hardware, switches, etc. but I don't know in my years, can you have 2 seperate adapters share an IP for fault tollerance, or would I have to down/up each of the nic's in the event of a switch failure.
View 1 Replies
View Related
Mar 4, 2010
I have to implement hardware redundancy.I have 2 linux machine for this and each have similar configuration/hardware. Lets say two machine Linux1 and Linux2. Currenty Linux1 have one NIC and it has 4 Ip address bind on it. Now I have to down the Linux1 and up Linux2 with same Ip addresses. Could it possible to configure all the Ip (same)address on both Linux1 and Linux2 and Linux1 have eth status UP while Linux2 have eth:y status down. I am trying it but on Linux2 machine I cant able to create multiple Ip interfaces with down status.
View 4 Replies
View Related
Jan 20, 2010
Can list options available for server redundancy? (i.e. fault tolerance methods so that if a server goes down another server can take over). Also is it possible to implement RAID1/disk mirroring across servers?
View 8 Replies
View Related
Apr 2, 2010
I have been using Trixbox CE for a couple of years and a client has asked me to setup a VOIP system with two phones and a couple of extensions. When he gets hit with a borage of phone calls I need to have the call that are behind the others to go the the next extension. I need redundancy if one Internet connection goes down and have the another kick in or failover. How does one configure Trixbox to failover to the other Internet connection and can someone give me a list of carriers in the Washington D.C area. Can someone point me in the right direction?
View 3 Replies
View Related
Jan 18, 2011
Our machine has two NIC on it but i'm only using one NIC, how do i make the most of the other one? I'm wondering if i can use it as a redundancy or load balanced but i dont know how.
View 2 Replies
View Related
Jul 15, 2010
I have several servers that we have bonded some NICs for rundancy and they will of course switch from primary to secondary NIC if connection state is lost to the switches they are physically connected to, but is there any way to be able to sense upstream connectivity (off switch) for each NIC and failover even though the NIC itself has a connection state to the switch it is plugged into? We are using Dell managed switches on VLANs with trunking.
View 3 Replies
View Related
Mar 24, 2010
I have four Red Hat 5 servers located in two different geographical sites. they are working active/active on each site.
Is there any software that I can use in order to have the four servers running Active/Active Active/Active in the same time, and if one site has been destroyed the other two servers in the other site handle the traffic?
Basically the traffic is a Web traffic.
View 10 Replies
View Related
Apr 23, 2010
I am familiar with active to active cluster failover and active to pasive failover, but what is network failover?
View 1 Replies
View Related
Dec 22, 2010
I recently added a second interface to my Ubuntu 9.10 server, I now have a dsl AND Cable connection for it, Im not trying to load balance or anything sophisitcated, heres my problem.
The machines networked, I put static entries in my dhcp servers and both interfaces are up and live with dhcp, and Ive tried with dhcp and static, same problem occurs.
But my problem is that services will only respond on one interface at a time, not both.
Anyone know what the heck is going on here?
Kernel IP routing table
Should I make them static and remove both gateways?
View 1 Replies
View Related
Sep 30, 2010
We have setup a High Available Cluster on two RHEL 5.4 machines with Redhat Cluster Suite (RHCS) having following configuration.
1. Both machines have Mysql server, Apache web server and Zabbix server.
2. Mysql database and web pages reside in SAN.
3. Active machine holds virtual IP and mounted shared disk.
4. We have also included a script in RHCS which takes care of starting Mysql, Apache and zabbix server on the machine which turns active when cluster switches over.
The above configuration holds good if Active machine goes down as a result of hardware failure or Reboot. What if, If any one service say Apache/Mysql/zabbix running on active hangs or become unresponsive.How can we handle this scenario ? Please advice.
View 3 Replies
View Related
Apr 15, 2009
I have been battering with FC10 and software RAID for a while now, and hopefully I will have a full working system soon. Basically, I tried using the F10 live CD to setup Software RAID 1 between 1 hard drives for redundancy (I know its not hardware raid but budget is tight) with the following table;
[Code]....
I set these up by using the RAID button on the partition section of the install except swap, which I set-up using the New partition button, created 1 swap partition on each hard drive that didn't take part in RAID. Almost every time I tried to do this install, it halted due to an error with one of the raid partitions and exited the installer. I actually managed it once, in about...ooo 10-15 times of trying but I broke it. After getting very frustrated I decided to build it using just 3 partitions
[Code]....
I left the rest un-touched. This worked fine after completing the install and setting up grub, reboot in to the install. I then installed gparted and cut the drive up further to finish my table on both hard drives. I then used mdadm --create...etc to create my RAID partitions. So I now have
[Code]....
View 2 Replies
View Related
Jan 20, 2011
I'm in need of some advise from you guys. I'm currently running a live production serverA, and last week it went down for a couple of hours which was really bad to say the least.
I've been thinking about building a mirror serverB that will rsync my data nightly. Now I don't want to load balance here, I just need to be able to switch to serverB when serverA goes down for any reason.
Would the best solution for this is to change my main nameserver entry when I want to switch ? I'm just curious if it will be a few hours or an instant change.
I thought I'd ask before attempting this live.
View 3 Replies
View Related
Nov 11, 2010
I have a dual-homed Debian server running squid, but not acting as a router. Simplied network diagram is below - there are other local hops between the gateways and the Internet.
Code:
(eth0 @ 192.168.44.2) <--> (Gateway1 @ 192.168.44.1) <--> Internet
(eth1 @ 192.168.55.2) <--> (Gateway2 @ 192.168.55.1) <--> Internet
Using Gateway1 gives a very fast, but not always reliable route to the Internet. Using Gateway2 gives a slower, but more reliable route to the Internet. The server uses Gateway1 as the default gateway.
I have written a script that pings three hosts on the Internet, and if all three are down, switches the default gateway to Gateway2. This part seems to be easy, but I'd like know if there is a way of routing a ICMP/ping out eth0 to a host, with all other traffic to the host going out eth1, so I can determine if the Internet is reachable via Gateway1 again.
View 2 Replies
View Related
Feb 9, 2011
I am using Centos. I have read places that you can use Drbd + heartbeat + nfs to make a simple failover NFS server.I can't find any document that works though. I've tried 20 or so, including some Debian ones.So, does anyone have any other ideas of how to do this?Point me in the right direction please.I want 2 nodes. One to be actively serving an NFS share The other to be ready for failover. If the first one goes out, the second takes over.Meaning, the filesystem is in sync, the IP must change, and NFS must come up
View 7 Replies
View Related
Jun 8, 2010
We are having a production setup where we are having one SAN storage and two RHEL machines. Now we have created a SAN LUN, say for example trylun. Now we have mounted the same SAN partition on both the machines of RHEL on the same mountpoint path say for example /trylun. After that we have installed RHEL Cluster suite to create a failover cluster.
Now we will be having one Ingres Database service for which data will be stored in SAN storage LUN mounted on both the machine say for example /trylun. When service on one machine will be down then RHEL Cluster Suite failover cluster will takeover and then it will start the same service on another node and handle the failover. Wether Ingres will run from node 1 or node 2 will not make any difference as both are using shared SAN storage i.e /trylun in our example. So same data storage will be used by both the ingres service on both the servers.
Now I have to simulate the same in my office test environment. But the problem is, in office test environment I will not have SAN server as it is additional cost. And I will have fedora operating system.
So I wanted to know is how can we create a shared file system like SAN in fedora (Is NFS a solution). And after creating the shared file system how can we create a failover cluster in fedora if we do not have Red Hat Cluster Suite.
View 1 Replies
View Related
Feb 15, 2011
My question is about setting up SMB and AFP failover between two servers. The plan is to have two servers both running CentOS with one acting as a primary node and one as secondary failover node. I have never set anything like this up before. In the past I have always worked with SAN's primary XSAN/StorNext. Both of which handle failover pretty much automatically. Unfortunately there isn't the budget on this job to install a SAN. Also this is only for temporary use for a week in a production office.
My thoughts where to run the two servers and use rsync on a cron tab to keep the data synchronised between the two. In an ideal world clients would log on to the primary and if that fails, seamlessly moved over to the secondary. I'm guessing however this is not possible outside of a SAN environment. So keeping the two servers synced and the clients manually moving over to the secondary manually is, I'm guessing, my only real option.
View 1 Replies
View Related
Nov 10, 2009
Have been tasked with a couple of Sunfire X2100 that I am slapping Fedora 11 onto for some high profile tasks around the office. Have two drives of the same size in each server and would like to have the two disks mirrored for redundancy. Admittedly I am new at Linux administration and am feeling over my head.
1. Can this be managed during the installation process of Fedora 11?
2. If yes, let me know the step by step please.
3. If no, I take it a cron job of rsync is going to be my best option.
4. Alternatives insights etc.
View 2 Replies
View Related
May 4, 2010
i have set up apt-cacher-ng and it is working fine.I have configured the clients using the synaptic gui, (configuration-preferences-network-set proxy...)Is there a way to configure the clients so that they use the proxy when it is available (at the office) and they fall back to using no proxy when the proxy cannot be reached?We have a lot of laptops at the office which are on the road a lot, in the office i want them to use apt-cacher-ng for updates and installation, when the users are not in the office they should be able to install software without having to change the synaptic conf...
View 2 Replies
View Related
Nov 30, 2010
My friend has a server with 2 ips, 1 primary and 1 secondary/failover. He has given me a shell account and I want to use ssh to route my home http traffic through it like a socks proxy. I connect to his server using the secondary ip like this:
ssh me@secondary_ip -p port -D forwarding_port
It builds a proxy, however it uses the primary ip of the server, not the secondary ip that I logged in with. When using irssi I've bound it to the secondary ip with no problem. If I try to use the -b flag I get the error: cannot bind: Cannot assign requested address.
how I can bind the ssh tunnel to the secondary ip?
View 5 Replies
View Related
Jul 3, 2011
I've configuration like this :
Quote:
I try to configure my /etc/rc.local with these setting :
Quote:
But whenever i check my router after reboot, still i can't connect to inet.
View 1 Replies
View Related
Jul 7, 2011
We run redundant switches that two nic's on each server connect to. We also run bonding on our servers. Because we have two switches, we can't run lacp or anything. If a switch goes into a crashed state where it doesn't pass traffic but still provides link, bonding thinks the interface is still up and thus will still send traffic through it. Does anybody know a better way to configure the fail over of the interface? This would be a similar situation to somebody using a media converter.
View 1 Replies
View Related
May 10, 2010
I have a linux machine, attached to a fibre channel SAN.
We're in the testing phases and we're attempting to get all of the bugs worked out before this goes live.
If i have my host streaming data to the storage device on the san (or from the device on the san) and simulate a path failure (by shutting down one of the host's ports on the FC switch), multipath does not pick up on another path until about 45 seconds have passed.
I can verify this by watching the statistic graph (which updates once per second) on the storage system.
I see iops running along rather nicely, and then they drop to 0 for 45 seconds, then pick right up to normal again.
This is a RehHat EL 5.5 system, with qlogic HBA's.
Am i being too picky? I'd expect multipath to recover in under 30 seconds, so as to not alarm host applications running on the linux host... 45 seconds seems like a long time to wait for a disk operation to complete.
Any tips on tuning Multipath, or the qlogic card? As it is, i've got the following options in my modprobe.conf.
alias scsi_hostadapter2 qla2xxx
Code:
My multipath.conf looks like:
Code:
View 3 Replies
View Related
Apr 26, 2010
I've been reading up on clustering a bit and want to create simple 2 machine cluster of which the 2nd one will turn on and take over traffic at the previous machine's IP (I'm aware there will be a couple minutes of downtime while the failover server boots). I've looked into doing a simple DNS round robin, but I think both machines would need to be online all the time for this to function correctly. I've also looked into linux-HA and GlusterFS but both seem a little intense for the simple failover I'm trying to achieve. One catch if approaching with DNS round robin... the server that I want to setup with a failover also operates as a DNS server. Anyone know the simplest way to complete this? One idea I had (that seemed like a bit of manual work): Create script that runs every 60 secs through CRON on firewall (running pfsense) and have it check if master-server is up. If it's not, it will send a WOL signal to the slave, which has a mirrored image of the first. the problem I have with that is I will also need to create a script to keep both synced properly which seems almost impossible if one is shut down until failover (my thought was periodic rsyncs.) Perhaps creating a FS to direct all files to for the master/slave would be the only way around that.
View 1 Replies
View Related
Aug 13, 2009
I am trying to setup multipath with failover policy on openSuSE 11. I have two qla2xxx HBA's installed and they appear to be working. Here is the output of "multipath -l" command
[Code]....
While testing, I pulled one of the two connection to SAN, and the connection failed over to second HBA connection to SAN. When I plug the cable back in, it does not fall back to original connection... It stays in failed state. Also, I noticed that failed disk (sdd disk) comes back as (sdg disk), which is probably why connection does not fall back to original HBA. But, when I run "/sbin/service multipathd restart" sdg disk shows as as enabled in multipath -l...
View 9 Replies
View Related
Mar 1, 2011
I am familiar with windows 2008 cluster servers, and I just started testing with centos cluster. I am creating a simple 2-node cluster, for a simple ping test.
Node 1: 10.0.0.1
Node 2: 10.0.0.1
Virtual ip: 10.0.0.10
So far, I can ping a virtual ip, and manually relocate it between the nodes, but I didn't figure out, how to do this automatically. So this is my question: How can I setup the cluster, to it automatically failover the a service to another node case one node fails?
View 1 Replies
View Related
Oct 27, 2010
I don't have much experience in clustering. And I'm deploying a cluster system on CentOS.But I don't know how long a node failover and another node take over those resouces to continue running service is good, fast or slow? 1s, 10s or
View 2 Replies
View Related
Oct 6, 2010
Where apart from ~/.kde4/share/apps/kmail does kmail keep account data, such as login data/names of pop/smtp servers? I wanted to install an entirely clean version of kmail, so I uninstalled/re-installed kmail via YAST. I manually deleted ~/.kde4/share/apps/kmail. After installing kmail I found that the account data of my Yahoo account were still listed in the kmail configuration panel. Shall I delete the Yahoo account within kmail prior to uninstalling the kmail package?
View 4 Replies
View Related
