High availability is an architectural consideration often involving degrees of redundancy to insure availability in case of system or component failure. Highly available systems are commonly implemented in situations where the risk outweighs the cost. Best practices such as change control, ...
1
vote
2answers
19 views
Improve automatic failover scenarios in SQL Server 2008
We have SQL Server 2008 set up in with a principal, mirror and monitor server, the mirror is synchronized and set to automatic failover. We recently saw a situation where we ran out of space on the ...
0
votes
1answer
19 views
How many mongod instances should I run with a 2 server replicaset setup?
Currently I've got server A and server B running with the following mongod instances:
Server A
mongod server (usually PRIMARY)
mongod arbiter
Server B
mongod server (usually SECONDARY)
When ...
-2
votes
2answers
56 views
Simple IP load balancer for web service that runs on Windows XP or Windows 7 Professional?
I've a closed code application that needs to connect to a web service that needs to run on XPs or Windows 7 (desktop). The application can only connect to a single IP address. The application is low ...
2
votes
3answers
65 views
Storage cluster for inexperienced admin
I'm a relatively inexperienced server admin who primarily works with Windows and a little bit of Linux. I'm the only admin of a small organization.
I'm looking for a way to have a high-availability ...
1
vote
1answer
44 views
Is there an ideal filesystem type for the MySQL database directory (/var/lib/mysql)?
I've used ext3 and ext4 in the past with no issues, but I've seen a lot of installations on XFS as well. What are the advantages of XFS vs ext4 vs ?? with respect to the /var/lib/mysql directory?
...
0
votes
1answer
40 views
HA Active/Active Squid configuration?
Hi all i would like to ask if someone have any experience into configuring squid within an active/active cluster.
First here is the actual configuration, which i would like to replicate to another ...
1
vote
3answers
78 views
How to mirror server with 150 GB of data
I have a linux server whic is used as web/file/svn/sql server. It is accessed by 100 machines for storing their code files on this server(svn/code/mysql).
The OS is on a 80 GB HDD. The data is on ...
-4
votes
2answers
67 views
Why do you have to rebuild RAID-1? [closed]
If RAID-1 is an exact mirror copy, why must you do a "rebuild" on a RAID-1 drive after the primary drive fails? Will the system suffer from any downtime if the primary drive fails?
Are there any ...
-3
votes
0answers
48 views
How I can have same IP Address for different Ethernet cards [closed]
I have a Fedora 16 Laptop that I like to put on a dock station with a ethernet cable for fast transfer of files but eventually I will be using it on the move around the company via wireless.
This ...
2
votes
1answer
98 views
which high availability model to choose for website (nginx/mysql)
We have 5 physical servers. All are identical. 16 gb ram, 4x146 10k sas in raid 10.
So, we need high availability. Current plan is following:
2 boxes with Heartbeat for load balancing. At this ...
0
votes
2answers
55 views
Server 2008 Failover
How do I ensure high availability of data on two physical servers in the event one were to fail?
I have two Dell T710s, both with Windows Server 2008 R2 Standard. My highest priority is to make sure ...
1
vote
0answers
12 views
Service fails to start when failover kicks in
I created a Windows Service which hosts a WCF application looking at/binding to the Clustered MSMQ
The Windows service was first installed on both nodes of the cluster.
I then created a cluster of ...
13
votes
4answers
279 views
When my A web server gets unplugged, how do I automatically redirect all the users to my B web server in another city, and vice versa?
When my A web server gets unplugged, how do I automatically redirect all the users to my B web server in another city, and vice versa?
A load-balancing switch does what I want, except I can't figure ...
0
votes
2answers
128 views
HAProxy NGInx SSL setup
I've been looking around different setups for a server cluster supporting SSL and I would like to benchmark my idea with you.
Requirements:
All servers in the cluster should be under the same full ...
2
votes
2answers
65 views
Swap DNS entry on failure
I'm building an application that requires high-availability. We currently run: 4 webservers, 2 varnish servers (both with Pound for SSL proxy), 3 Cassandra nodes.
The varnish servers are used as ...
1
vote
3answers
92 views
Shared PHP Sessions in Load Balanced httpd environment
I have two httpd servers running PHP on RHEL 5.7. Initially I was sharing PHP sessions between the servers using a common NFS share that was hosted on a third server. This was causing slow downs and ...
0
votes
0answers
73 views
Percona XtraDB Cluster with GlusterFS
We are deploying a GlusterFS cluster with 4 nodes, and we want to deploy the Percona XtraDB Cluster on top of it with 4 nodes, each node will have a mounted folder from the GlusterFS, each mount will ...
0
votes
1answer
62 views
SQL Server High Availability - Mirroring with MSCS?
I'm looking at options for high-availability for my SQL Server-powered application.
The requirements are:
HA protection from storage failure.
Data accessibility when one of the DB servers is ...
6
votes
1answer
222 views
Avoiding SPOFS with GlusterFS and Windows
We have a GlusterFS cluster we use for our processing function. We want to get Windows integrated into it, but are having some trouble figuring out how to avoid the single-point-of-failure that is a ...
6
votes
3answers
205 views
Seeking distributed, fault-tolerant, networked block storage
I'm looking for a distributed, fault-tolerant network storage system which exposes block devices (not filesystems) on the clients.
A client's block device should write simultaneously to several ...
0
votes
1answer
81 views
DNS failover in a two datacenter scenario
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 ...
1
vote
2answers
186 views
What happens if an OpenStack cloud controller dies?
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 ...
2
votes
5answers
133 views
How to make AD highly available for applications that use it as an LDAP service
Our situation
We currently have many web applications that use LDAP for authentication. For this, we point the web application to one of our AD domain controllers using the LDAPS port (636).
When we ...
0
votes
2answers
58 views
Exchange 2010 roles on multiple VMs
I'm looking for some guidance / best practices on how to setup high availability on my exchange 2010 SP2 install. I'd like to install each role in a different VM on 1 server, then have a second server ...
1
vote
1answer
119 views
Is it better to disable Keep-Alive in IIS 7 for high traffic web applications?
The advice below applies to Apache, but it seems generic enough to apply regardless of system. My architecture is 3 web servers behind a load balancer. My IIS servers currently have keep-alive enabled ...
0
votes
2answers
72 views
Linux High Availability
I have two Linux Active/Passive nodes on which i have the same simple processing application(not webapp). I just need to have a HA cluster when one machine is down the application on the second takes ...
0
votes
1answer
288 views
How to setup STONITH in a 2-node active/passive linux HA pacemaker cluster?
I am trying to setup an active/passive (2 nodes) Linux-HA cluster with corosync and pacemaker to hold a PostgreSQL-Database up and running. It works via DRBD and a service-ip. If node1 fails, node2 ...
1
vote
2answers
45 views
How can I achieve ACID on multiple physical front-end servers
I'm looking for a way to have several physical front-end servers with ACID data access.
In a setup where several servers gets load-balanced using DNS-round robin, the problem is that whatever server ...
0
votes
2answers
67 views
postfix: try backup mx server if local delivery fails
I have a problem when the mail server can't access the shared storage and then the emails start piling up in the mail queue. Now I would like postfix to try and send the emails to the secondary mail ...
7
votes
5answers
414 views
Setup for high availability virtualized environment
For a project I have the task of planning a high availability setup for a web shop and CMS system. However, of course the project is on a tight budget. So a high end solution might not be in the ...
1
vote
0answers
76 views
Memcached and repcached not replicating 2 master servers
I have memcached-1.2.8-repcached-2.2 installed on memcached on centos.
They install went great and when i start memcached i get:
replication: connect (peer=192.168.1.2:11212)
replication: marugoto ...
1
vote
0answers
87 views
Ganeti and automatic failover
I'm building a simple 2-node cluster with Ganeti+DRBD... What is the recommended way to setup automatic failover?
I'm used to Heartbeat, but they say it should be avoided with my setup.
1
vote
0answers
132 views
Replicating beanstalkd for High Availability
Title says it all.
Does anyone know of a way to replicate beanstalkd such that if a beanstalk server went down, others slaves could take over?
Here's one approach I thought of:
I could make ...
1
vote
2answers
135 views
How Ganeti deals with Fencing
I found out that proxmox doc says a lot abou Fencing. I haven't found anything about it in Ganeti doc. Also I screeched Ganeti Google Group Archive and I found similar question but answer was that ...
0
votes
1answer
183 views
Best RAID setup for DRBD
I would like to setup a two nodes PROXMOX cluster with DRBD storage. The nodes will be connected by gigabit ethernet. What would be the best storage setup in terms of reliability, performance and ...
0
votes
0answers
70 views
Reliably hosting job queue and shared filesystem on AWS
Currently I've been working on a project where we're using both a job queue like Beanstalkd and NFS for sharing files.
The problem with something like this on AWS is that the instance attached to the ...
1
vote
1answer
94 views
What happens to additional requests when HaProxy hits its max session limit
I have HA proxy load balancing across 3 web servers. The session limit is set to 200 and I am seeing the "Curr sessions" hit the limit. Am I losing traffic or are the additional requests queued up and ...
1
vote
1answer
120 views
MySQL cluster for Drupal?
We have a pretty busy site based on Drupal and I was thinking of introducing some form of clustering for HA and Load balancing.
However, http://drupal.org/requirements says: Drupal supports MyISAM ...
6
votes
2answers
140 views
Is there a way to force heartbeat to add new ip addresses to the system without a full restart?
We utilize heartbeat for High Availability. I'd like to add an additional ip address to the heartbeat cluster, but I don't want to do a full restart of the cluster in the process. Is there a signal ...
4
votes
2answers
240 views
What is the difference between keepalive and heartbeat?
I want to structure a high available server cluster . Now I want to know detail about keepalive and heartbeat, what is the difference between both, and How to choice one.
0
votes
1answer
38 views
update of mysql server without break
Hy,
I want to update my databases on my mysql server, but for now i usually take my server down before to the update.
I wonder if there is any solution to make the update without any disruption of ...
2
votes
2answers
123 views
High Availability with 3 servers: To virtualise or not?
We're changing hosts for our SAAS app (IIS+MSSQL) and have an opportunity to redesign the infrastructure. Either stick with what we have (which works well) or virtualise with vSphere.
Current:
2x ...
1
vote
4answers
96 views
High Availability Options for MSMQ
We plan to develop a highly available system based on Microsoft Message Queuing (MSMQ). Currently we are collecting high availability options for MSMQ. We plan to use Windows Server 2008R2 as the ...
0
votes
0answers
50 views
SAN — Servers and physical connections [closed]
I have a SAN for which I pretend to connect more Servers than the physical connections available. What alternatives exists to provide the service to all servers? Could you please tell me some examples ...
0
votes
0answers
29 views
Do ISPs or Telcos provide uptime or availability alerts via Twitter? What #hashtags are used? [closed]
I'd like to search twitter for network availability reports, or get reports from telco providers regarding the same.
What twitter accounts should I subscribe to, what #hashtags will help me search ...
0
votes
1answer
123 views
High availability architecture for a small business
We are a small startup. In our current setup we have a dedicated server in a remote location. Our website and applications are hosted in that server. Website and some applications are in PHP and the ...
2
votes
3answers
538 views
Ganeti vs Proxmox
I'm system administrator in small software house. I'm going to virtualise our servers. The main reason for doing this is providing highest possible uptime, but probably it will also increase resources ...
7
votes
2answers
183 views
Multi-site high availability
We have a SaaS application that we need to be highly available. We already have an expensive, well-maintained Hyper-V failover cluster, but today the datacenter where we host that cluster had a ...
-1
votes
2answers
215 views
corosync active-active with 2 virtual IPs - clone constraints task
I have DNS roundrobin on 2 virtual IP in front of service. (Among others the service tested was: apache, nginx, varnish, postfix, … It really does not matter. Let's call it just service.)
I ...
1
vote
0answers
78 views
repcached broken sync - memcached high avalaibility
I have been using repcached (memcached-1.2.8-repcached-2.2)to store php sessions in order to have a highly available memcached. Everything runs perfect, I can restart a daemon without losing sessions.
...
