Hi People, I want a scenario where I have two servers that appear as one server (one IP) to the outside world, with both servers having *exactly* the same data. So in case one server falls into a pond somehow, I woun''t even loose a ping from my clints. I have been adviced that I can do this using XEN. I''ve used debian linux alot for my server backends, so I pretty much know my way around linux (not GUI though). I understand XEN is virtualization software (ie host/guest) but I understand it can do much more (like the scenario I am asking for). Any help from the experts? Anyone? Thanks, -- Jangita | +256 76 91 8383 | Y! & MSN: jangita@yahoo.com Skype: jangita | GTalk: jangita.nyagudi@gmail.com _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Jangita wrote:>I want a scenario where I have two servers that appear as one server >(one IP) to the outside world, with both servers having *exactly* >the same data. So in case one server falls into a pond somehow, I >woun''t even loose a ping from my clints. I have been adviced that I >can do this using XEN. I''ve used debian linux alot for my server >backends, so I pretty much know my way around linux (not GUI though). > >I understand XEN is virtualization software (ie host/guest) but I >understand it can do much more (like the scenario I am asking for).Xen on it''s own isn''t really relevant to you, it doesn''t do what you are asking for - but it can be *part* of a setup. What you are talking about is a HA (High Availability) setup and I''m sure there will be people along fairly soon to point you in the right direction as there are few people on here involved in that sort of thing. -- Simon Hobson Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed author Gladys Hobson. Novels - poetry - short stories - ideal as Christmas stocking fillers. Some available as e-books. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, 2010-09-02 at 17:05 +0100, Simon Hobson wrote:> Jangita wrote: > > >I want a scenario where I have two servers that appear as one server > >(one IP) to the outside world, with both servers having *exactly* > >the same data.> What you are > talking about is a HA (High Availability) setupIf what you want is really just one server backed by a hot spare, then you don''t need Xen at all. The easiest way to do this is using heartbeat for high availability and DRBD to replicate the data. Heartbeat v1 does this very well and is fairly easy to understand. Unfortunately, all the HA developers want everyone to run the latest version of heartbeat (v2 or v3) or corosync, with pacemaker and despite what they sometimes say, this is a very large basketball to swallow. It is massive overkill just for a pair of hot spare servers with a shared IP address. But it is difficult to find anyone who will help you with heartbeat v1 since it is "obsolete", but you may be able to figure it out yourself. The official documentation for HA on Linux is at http://www.linux-ha.org/ and http://www.drbd.org/ --Greg _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Dennis Storm - Drecomm BV
2010-Sep-02 16:38 UTC
Re: ***SPAM*** [Xen-users] 2 Servers: Exact Copy
You can do this with xen, but also with machines that run directly on the iron. Check out documentation about "vrrp" and "keepalived". What would be handy is shared storage between clients. For that, look into "drbr active/active" Kind regards, Dennis Storm - Senior Systems Engineer Telefoon: (050) 577 58 22 (toestel 9701) Mobiel: 06 4141 0181 E-mail: d.storm@drecomm.nl Drecomm BV "Internet Intelligence" Opensource Internet Oplossingen Vestiging Groningen: Hoendiep 208 9745 ED Groningen T: +31 (0)50 577 58 22 F: +31 (0)50 577 58 23 Vestiging Rotterdam, Walenburgerweg 46, 3033 AD Rotterdam Vestiging Amersfoort, Bergstraat 25, 3811 NE Amersfoort On 02-09-10 17:22, Jangita wrote:> Hi People, > > I want a scenario where I have two servers that appear as one server > (one IP) to the outside world, with both servers having *exactly* the > same data. So in case one server falls into a pond somehow, I woun''t > even loose a ping from my clints. I have been adviced that I can do > this using XEN. I''ve used debian linux alot for my server backends, so > I pretty much know my way around linux (not GUI though). > > I understand XEN is virtualization software (ie host/guest) but I > understand it can do much more (like the scenario I am asking for). > > Any help from the experts? Anyone? > > Thanks,_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On 02/09/2010 6:29 p, Greg Woods wrote:> >> What you are >> talking about is a HA (High Availability) setup > > If what you want is really just one server backed by a hot spare, then > you don''t need Xen at all. The easiest way to do this is using heartbeat > for high availability and DRBD to replicate the data. Heartbeat v1 does > this very well and is fairly easy to understand. Unfortunately, all the > HA developers want everyone to run the latest version of heartbeat (v2 > or v3) or corosync, with pacemaker and despite what they sometimes say, > this is a very large basketball to swallow. It is massive overkill just > for a pair of hot spare servers with a shared IP address. But it is > difficult to find anyone who will help you with heartbeat v1 since it is > "obsolete", but you may be able to figure it out yourself. > > The official documentation for HA on Linux is at > http://www.linux-ha.org/ and http://www.drbd.org/ > > --GregThanks I heard of remus http://wiki.xensource.com/xenwiki/Remus that could do something similar. Let me look at your suggestions. Many thanks to the list. -- Jangita | +256 76 91 8383 | Y! & MSN: jangita@yahoo.com Skype: jangita | GTalk: jangita.nyagudi@gmail.com _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On 03/09/2010, at 5:23 PM, Jangita wrote:> On 02/09/2010 6:29 p, Greg Woods wrote: > >> >>> What you are >>> talking about is a HA (High Availability) setup >> >> If what you want is really just one server backed by a hot spare, then >> you don''t need Xen at all. The easiest way to do this is using heartbeat >> for high availability and DRBD to replicate the data. Heartbeat v1 does >> this very well and is fairly easy to understand. Unfortunately, all the >> HA developers want everyone to run the latest version of heartbeat (v2 >> or v3) or corosync, with pacemaker and despite what they sometimes say, >> this is a very large basketball to swallow. It is massive overkill just >> for a pair of hot spare servers with a shared IP address. But it is >> difficult to find anyone who will help you with heartbeat v1 since it is >> "obsolete", but you may be able to figure it out yourself. >> >> The official documentation for HA on Linux is at >> http://www.linux-ha.org/ and http://www.drbd.org/ >> >> --Greg > Thanks I heard of remus http://wiki.xensource.com/xenwiki/Remus that could do something similar. Let me look at your suggestions. Many thanks to the list. >If you want the fail over to be transparent to the end users then Remus is what you''re looking for and (I think) is included in Xen 4.0.1. Kemari is a similar project. These provide the same sort of redundancy as vmware fault tolerance. Heartbeat and DRBD will provide a failover server which can start automatically if the active server fails, but it will look like a server restart to end users. This is more akin to vmware high availability, but doesn''t sound like what you were after. Jeff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users