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Questions tagged [redundancy]

Redundancy is the duplication of critical components or functions of a system with the intention of increasing reliability of the system, usually in the case of a backup or fail-safe.

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Redundant Power Supply Sloshing (If sloshing is the right word)

I have a Supermicro Redundant Power Supply with two units in it. I also have two UPS units, one for each of the Power Supplys. I was watching the LCD on the UPSs for the watt usage. The total watts equal about 400 Watts. This is where it gets…
xriri
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VMware vSphere cluster design for site redundancy

I have a question about the best design for site redudancy when using vSphere clusters. A bit of background info about our situation first though. We are a medium-sized company with two main offices, located in different countries. Our networks are…
Stefan Radovanovici
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Increase reliability by partitioning disks of different size?

I understand ZFS would prefer all disks carrying the same size. However, in the case that I have two disks with different size (1TB and 1.5TB), I'd like to have certain redundancy, but not mirroring. So I chop two disks into 5 partitions, with each…
python152
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Hot spare host vs cold spare host?

We have several hosts where we have an identical hot spare host, which is patched and updated so it is very close to have to same software and config. In case of failure the network cable is switched and the DHCP server is updated with the new MAC…
Jasmine Lognnes
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DRBD for HA Server in Small Office Questions

Backround: We are in need of a HA server in a small office environment and are looking at DRBD to provide it. We only have about 100GB that needs to be on the HA server and server load will be extremely low. The data will probably increase about…
Damon
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A-Record Failover?

I have a Fortigate 100D with 2x BT Business Infinity Fibre connections acting as WAN1 & WAN2. The BT lines come with 5 static public IPs each and I have my DNS hosted through CloudFlare pointing at a static IP on one of WAN connections. (Say you do…
Myles Gray
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Local to Remote Webserver Failover

Short and sweet, I don't suppose you'll need more detail than this: We host our website on an in-house webserver. A catastrophe has and will happen again where communication from the web into/out of our building ceases. When this happens, we'd…
anonymous coward
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Is it possible to make redundancy on HAProxy server?

I am going to use HAProxy as a load balancer that will balance requests on 3 application servers. But what if balancer server (HAProxy) fails at some point? I was thinking of cloning the first balancer, so if the main one fails the other will take…
wael34218
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If a RAID controller fails, does it disrupt service until it's replaced?

If I have 2 drives in a RAID 1, and the Raid Controller fails, does that mean the websites on the server will have downtime until the controller is replaced? Or does everything still carry on as software raid automatically until the faulty raid card…
Winker
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How to setup redundancy for AWS Elastic Load Balancers?

In the spirit of redundancy and fail-over, I would like to know some strategies on setting up AWS Elastic Load Balancers for DR, that is, if this is really an issue? (A single ELB would LB traffic to 1..* regions.) I'm asking because in a proposed…
ElHaix
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Linux console is unusable when LDAP server is down

When our OpenLDAP server lost power the CentOS machines' console became nearly unusable. We were trying to login with a local account, but each command would take minutes to return. Even simple commands like ls were just sitting there. This does…
csexton
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How do I configure NAT rules when using ASA IP-SLA when leveraging post-ASA-8.3 NAT syntax?

We are currently running ASA9 at a location with redundant ip connectivity. We'd love to configure ip sla so that internet access survives a single carrier outage. I'm aware of the ip sla commands, however when I've tried to prepopulate the…
Peter Grace
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How do you set up redundant servers?

To the sysadmins out there, I'm trying to get an idea about how you go about maintaining redundant servers for small projects. The modest number of servers in my mind is two, and three main essential services come to mind: HTTP, mail and DNS. How do…
ezequiel-garzon
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SQL Server clustering options

Can anyone give an high-level overview of the options available for SQL Server clustering, their pros and cons? Is it better to use Microsoft Clustering services or SQL Server native clustering? Does that choice even apply to the latest SQL Server…
Tomalak
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Getting Started with NIC and Switch Redundancy

Currently with my servers, they all or almost all have 2 nics with one in use. Each NIC is is of course connected to a single switch. What do I need to do to make this redundant in that both NICs are used and connected to different switches, but…
Kyle Brandt
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