user1034912's questions

I am designing a simple fail over system with just a primary and standby server. The main one will be in our office, while the standby will be on the cloud. I was reading about virtual IPs and how they provide 'failover' typically for load balancers.

My question:

How are they able to switch so fast?

My limited understanding of DNS data is that they are cached on dns servers worldwide. Surely, it will take time to propagate any changes.

I am setting up a high availability load balancer. I found this tutorial from Digital Ocean which says that two load balancers can share a common floating IP.

https://docs.digitalocean.com/products/networking/floating-ips/#how-to-implement-an-ha-setup

What is this floating IP and how does it work?

Can one set it up by one's self (without using Digital Ocean)

I intend to create a SaaS with two Load Balancers. If one load balancer goes down, 'MySaaSApp.com' will point to the other load balancer. Can such be accomplished through DNS Records alone? Thanks!

I have been tasked to create a local university database for a Malaysian Client.

The client is requesting us to use Amazon Web Services as they bought into the marketing hype. I told them that AWS' closest servers are in Singapore, and it is probably better to use local Malaysian servers to ensure speed.

They are saying that a lot of malaysian companies use AWS and they seem to have no problem with speed. One example is https://www.iproperty.com.my which is the largest real estate website in Malaysia and they have their servers located in the USA.

I'm a little confused here..... seems like being "local" has no speed benefit.... to such that it maybe a myth to say that 'local servers are faster'...

What do you guys think?

I'm learning about Active Directories.

I understand when a computer wants to join a domain, it needs to change his DNS settings to that of the Domain Controller IP address. Then only it can see the Domain Controller, and join in

I find this rather weird and I can't get my head around this.

Why can't the DC connection work like any other client-server application? I.e. the client specifies the IP address of the server, Click connect, and joins the domain.

My Question

1. What's the logic behind this?

2. What happens when one wants to use a different (both primary and secondary) DNS server?

A Windows ID (such as MyDomain\someuser) will have a unique SID (such as S-1-5-21-1695517229-881958489-217698969-1001)

The ID is used during login, which confirms that it too is unique in nature.

What's the purpose of the SID then?

Seems like a redundant primary key to me!

How do I know if the following RAM is SODIMM size?

Manufacturers never make it simple to buy...

https://www.scorptec.com.au/product/Memory/DDR4/79106-KD4AGU880-32A160T http://www.klevv.com/ken/products_details/memory/Klevv_BoltX.php

Today I was shopping for the most basic dell rack server which is the R240.

Ironically, they are still using HDD 7200 RPM, with no option for SSD in their selection; and we're approaching 2020!

https://www.dell.com/en-au/work/shop/servers-storage-and-networking/poweredge-r240-rack-server/spd/poweredge-r240/4er2401101auoo_vi_vp

My question is simple

1. Why is this so? (optional)
2. Can I buy a cheap SSD (like the cheap 1TB 2.5" SSD on ebay) and swap them on the R240?

Thanks

I was developing a system which requires connection between two computers. I decided to connect the two machines together via direct ethernet cable.

My boss didn't like it as there is no firewall in between. The two computer are both connected to separate corporate networks. The cable would essentially bridge these two networks posing security concerns

My boss then decided that we purchase a CISCO firewall just to connect the two machines. I told him why not use windows firewall? Wouldn't that be sufficient? The answer: It's not standard!

Is there any particular standard that demotes Windows Firewall?

Thanks

In Windows systems (particularly Windows Server 2008R2 which I an using), sometimes when I add a local user to a local group, the user needs to log-off and log-on back again before this new group is registered to him.

But Sometimes as well, the group registration is done immediately.. without the user having to log-off and log-on back again..

why is this so?

My Experiment

• So I set up a simple network with Two computers. Both on the same Work group.
• I created a LOCAL user 'A' with pasword 'A' in Computer 1.
• And then I created an identical named LOCAL user 'A' with identical password 'A' on Computer 2.

My Observation

• What I notice is that when I'm logged in as 'A' in computer 2, I am allowed network access as 'A' in Computer 1. E.g. when browing 'A' shared folders.

My Thoughts

• This is ironic as even though they are the identical in name, they are acutally two different LOCAL users on two different computers!
• This to me can be a security hazard. What if coincientially a Person has the same username and password in computer 2 thus incorrectly given access to Computer 1?

My Question:

• What is this sharing of username and password called?
• How come identical name and authentication between two windows PCs on same network works?
• How do we enable/disable this sharing of identical LOCAL usernames and passwords between two computers?

I've also realized that this works during DCOM calls as well.

Thank you for any answers

I will be installing a Database System on an Offshore Oil Platform (rack Servers). They have very limited hardware and space therefore sending up a backup infrastructure is not possible. Sending backups via FTP too is not possible as they do not even have a file server.

I was thinking of backing up the SQL database on to a Portable USD Hard Drives. The USB Hard Drives will be plugged in directly on the server at all times. Once a week, they will swap the hard drive with a fresh /older one.

Is it a good Idea to do this? If not can you propose a better solution?

In C:\Program Files\Microsoft SQL Server\, I'm seeing many sub folders such as

• 80
• 90
• 100
• MSAS10_50.MSSQLSERVER
• MSRS10_50.MSSQLSERVER
• MSSQL10.50.MSSQLSERVER

What are these sub directories for? Are they for each SQL Server instance? Can we delete the folders?

Youtube as we know, is massive. It has thousand of concurrent users streaming at least 2 megabytes per video. Obviously, that gets to be a lot of traffic... far too much for any one server.

What networking technologies allow pushing 4 billion videos a day?

I'm installing a highly critical system. If the system fails, the users wants data up to the last minute.

To achieve this, I was thinking of running Transaction Log Backups + FTP every minute. Has anybody done this before? Is this the best way to achieve the 1-minute data loss tolerance?

Appreciate any advice,

Thanks!

My SQL Server Machine has 6GB of RAM but the database size is 20GB. The Database is mainly an events log, clustered-indexed by time.

The clients are mostly interested in the latest data. They want it to be super fast when querying these latest data.

As SQL Server loads itself into server memory, is there a way to instruct SQL to pre-load only the latest data into memory?

People keep telling me that in order to improve an SQL server's performance, buy the fastest hard disks possible with RAID 5, etc.

So I was thinking, instead of spending all the money for RAID 5 and super-duper fast hard disks (which isn't cheap by the way), why not just get tonnes of RAM? We know that an SQL server loads the database into memory. Memory is wayyyy faster than any hard disks.

Why not stuff in like 100 GB of RAM on a server? Then just use a regular SCSI hard disk with RAID 1. Wouldn't that be a lot cheaper and faster?

What's the benefit of performing regular database integrity checks? Can't we just perform it when there's a problem?

Quick question! I heard that we should never shrink our databases. However, does the same rules apply to compressing our SQL backup?

Thanks

All I have is just a Word Document inside the CD.

My company purchased an SQL Server a long time. We contacted the ex-employee and he mentioned to us that the license can be found inside the SQL Installer CD.

When we opened the SQL CD, we saw the license file. It was just a simple word document which can be edited, copied and easily distributed. There was no reference to our company name or any signatures in the license.

So, If Microsoft actually audits us, how would they know that our SQL Copy is genuine?