Are availability groups required for AlwaysOn

Beginning a project to create an HA SQL server environment. We are limited to using SQL Server Standard edition, currently 2016. From what I have found, AO(AlwaysOn) for standard edition limits you to basic AG (availability group) and thus only 1 database per AG. This is going to be tough since most of our SQL instances contain 30+ databases. Can you implement AO without AGs? Are there other ways to configure AO to address our needs? All databases on any of our instances are managed similarly and thus wouldn’t need the flexibility that managing at an AG provides.

Does a DDOS attack on an application using CDN have to first bring down all the involved CDN servers to affect the application’s availability?

CDN are said to absorb and mitigate the Denial of Service and DDOS attacks. Consider an application that uses a CDN provider to deliver its content. So if an attacker tries to bring down such an application using DOS or DDOS, the flood of requests made during such an attack will go to the CDN servers. Will such a DDOS attack have to completely bring down all the CDN servers serving this application’s content before impairing the origin server completely?

High Availability Boot processes and only using code-signing certificates

High Availability Boot (HAB) is a technique described here in an NxP application note. This is best summarised as:

HAB authentication is based on public key cryptography using the RSA algorithm in which image data is signed offline using a series of private keys. The resulting signed image data is then verified on the i.MX processor using the corresponding public keys. This key structure is known as a PKI tree. Super Root Keys, or SRK, are components of the PKI tree. HAB relies on a table of the public SRKs to be hashed and placed in fuses on the target.

The procedure burns Super Root Key (SRK) fuses using a software tool called srktool. In it’s proper use, I would use an SSL certificate with the OID set for code-signing. This would have an oid of 1.3.6.1.5.5.7.3.3.

However, there doesn’t appear to be anything that stops me from using a certificate that is created for other purposes, e.g. for client authentication with the OID of 1.3.6.1.5.5.7.3.2.

The problem is that if I have two certificates from the same CA:

  1. Code-signing certificate
  2. Client certificate

I could sign the image with the code-signing certificate. If I could update the public key on the target device, then it would be possible to sign it with the client certificate and it would be accepted as valid.

The only option is use different CAs for both code-signing and client certs. I’m wondering if there’s some way to check the OIDs?

Different Maximum server memory across Availability Replicas

I have a scenario in SQL Server 2014 AlwaysOn High Availability where other services are running in one of the Secondary read-only replicas.

These services obviously demand additional memory. Is there any good practice or specific reason why SQL Server should have the same memory configuration across different replicas?

Availability Calendar UI/UX Approach

I’m currently working on an availability calendar where the users will be able to see the available slots of a tutor that he has previously set.

Users can book a lesson by clicking on an available slot. I have come up with a basic calendar structure for this. However, It already looks like a mess. Appreciate your ideas to re-arrange design of the slots.

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High availability cluster

quick question about how high availability cluster works. If i were not mistaken, If I setup 3 high availability servers, all traffic will only be processed on single server right? then if the first server died then it goes to the second server? or do they have a load balancer to distributes the workload equally to all of the server?

Do I need “New SQL Server Failover Cluster installation” to run Availability groups with manual failover?

I’m trying to set up a test environment here to learn more and apply this on our production environment.

I’ve created and installed the Windows Cluster with CLuster manager. Now I’m going to install SQL Server Enterprise 2014 on both machines and create HA with then, with availability groups. The failover will be manual. They will be in synchronized data transfer.

My question is, Can I normally install “stand-alone installarion or add…” the SQL server, or I need to use “new sql server failover cluster installation”.

I cant find anything about this on the internet.

Im going to install sql server on both nodes that will be configured in the cluster.

SP Online: Search and offline availability not visible under Site Settings [I am Site Admin]

This is very strange issue, I used to have option of ‘Search and offline availability’ under Site Settings, but suddenly it got disappeared.

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Details:

Site: SharePoint Online

Permission: Site Collection Administrator & Site Owner

Any reason for this behavior ?