DNS Interview Questions and Answers Windows Server

What is Domain Name System (DNS)?
Domain Name System is a service to resolve the Name to IP Address and IP Address to Name, DNS also used to locate servers, computers and services on your network and DNS is backbone of Active Directory that can be installed on windows server as a standalone or Domain Controller

What is Static and Dynamic DNS Record?
Manually created DNS entry called static record and the record created automatically by the system/DHCP itself called Dynamic DNS Record, static records are not easy to manage as the IP adress changes will not update automatically, we have to update manually

What is Dynamic DNS (DDNS)?
Dynamic DNS or DDNS is a method of updating a DNS record, DDNS is preferred most of the organization since it’s easy to maintain and you always get the latest updated IP address of the servers and computers

What are the record types in DNS?
DNS has many types of records, A record or host records are mostly known to everyone, will explain all the record types in DNS

A (Address) Maps a host name to an IP address, Compute1 pointing to 192.168.100.100, When a computer has multiple adapter cards and IP addresses, it should have multiple address records.
CNAME (Canonical Name) Sets an alias for a host name. Record pointing to different record like www.support.windowstricks.in can have an alias as www.windowstricks.in, so both the records are pointing to same page

MX (Mail Exchange) Specifies a mail exchange server for the domain, used for mail delivery which allows mail to be delivered to the correct mail servers

NS (Name Server) Specifies a name server for the domain, which is authoritative servers for the respective DNS Zone and allows DNS lookups within all DNS zones

PTR (Pointer) Creates a pointer that maps an IP address to a host name for reverse lookups.
SOA (Start of Authority) Declares the host that is the most authoritative for the zone and, as such, is the best source of DNS information for the zone. Each zone file must have an SOA record (which is created automatically when you add a zone)


What is Caching Only Server?
Caching-only servers are those DNS servers that only perform name resolution queries, cache the answers, and return the results to the client. Once the query is stored in cache, next time the query in resolved locally from cached instead of going to the actual site.

What are a Forward and Reverse Lookup?

• Forward Lookup: Searching for A record, all the name query is send to the DNS server against to IP address, it is generally said a forward lookup.
• Reverse Lookup: Searching for PTR records whicho provides a reverse lookup process, enabling clients to use a known IP address during a name query and look up a computer name based on its address

What is Primary DNS zone?
This is the read and writable copy of a zone file in the DNS namespace. This is primary source for information about the zone and it stores the master copy of zone data in a local file or in AD DS. Dy default the primary zone file is named as zone_name.dns in Windows\System32\DNS folder on the server
If its AD integrated zone then all the records are stored in Domain partition on the Domain Controllers

What id Secondary DNS zone?
This is the read only copy of a zone file in the DNS namespace. This is secondary source for information about the zone and it get the updated information from the master copy of primary zone. The network access must be available to connect with primary server. As secondary zone is merely a copy of a primary zone that is hosted on another server, and secondary zone cannot be stored in AD


What is stub DNS Zone?
A stub zone is a read only copy of a zone that contains only those resource records which are necessary to identify the authoritative DNS servers for that particular zone, stub zone also used like DNS Forwarding and its practically used to resolve names between separate DNS namespaces. This type of zone is generally created when a corporate merger or acquire and DNS servers for two separate DNS namespaces resolve names for clients in both namespaces.

A stub zone contains:
The start of authority (SOA) resource record, name server (NS) resource records, and the glue A resource records for the delegated zone.
The IP address of one or more master servers that can be used to update the stub zone

What is Aging and Scavenging?
Aging and Scavenging is a DNS server service which supports a mechanism for performing clean-up and removal of stale resource records which can accumulate in zone data over time. It helps to maintain the dynamic DNS environment by regular deletion of stale resource records from the DNS database. Some problems associated with stale records are: unnecessary space utilization long zone transfers, wrong resolution of the client query due to stale data, and accumulation of stale records on the DNS server can degrade its performance. These stale records problems can be resolved by the aging and scavenging features. Before using aging and scavenging features of DNS some conditions needed are:
1) Aging and scavenging features must be enabled on the DNS server and on the zone. By default, they are not enabled.
2) Resource records must be added dynamically to the zone or manually modified to be used in operations of aging and scavenging.

Aging
Aging is the process of identifying stale DNS records. It uses two intervals:
1) Non-Refresh interval
2) Refresh interval

Non-Refresh interval
This is the time period in which the resource records cannot be refreshed. It can be used to reduce the replication traffic in this time period to avoid the replication of the same information again.

Refresh interval
This is the time period in which the resource records can be refreshed.
Resource record refresh: This is a DNS dynamic update without changing the hostname and IP address.
If the non-refresh interval and refresh interval are 7 days, then the resource records can be considered as stale if not refreshed after 14 days. If the non-refresh interval and refresh interval are elapsed, then the resource records can be refreshed as long as they are not removed from the DNS zone. Aging uses a resource record time-stamp to identify if the record is stale or not.
Resource records having timestamp zero: These records are static records that are not stale records.
Resource records having timestamp not equal to zero: These records are dynamic records which represent the hour of the last refresh date.

Scavenging
Scavenging is the process of removal and clean-up of stale resource records from the DNS zone. The stale resource records will be removed only if the scavenging is enabled on the resource record,  where the resource record exists and at least one DNS hosting where the primary copy of the resource records exists.
Scavenging can be set in three places:
1) Individual record
2) Zone
3) Server
If scavenging is set on zone it will work only for dynamic records. It will work for manual entries only if it’s enabled for the zone. Once scavenging is set on zone this will enable it on DNS servers. The DNS server where the scavenging option enabled is responsible to scavenge the record. The server will log a DNS event 2501 to indicate the number of scavenging record and it will log a DNS event 2502 if no record where scavenged.

Scavenging formula:

Record timestamp+no refresh interval for zone+refresh interval for zone

If the sum of these values are greater the server time (current date and time on the DNS server) no action is taken and records are not deleted from the zone. If the sum is less than server time the records are deleted.

Aging and scavenging process for a sample record
Consider a DNS host “host-a.example.microsoft.com” register its host resource record on the DNS server where aging and scavenging are enabled. The DNS server set a time stamp for this record based on the current server time at the time of registration. The DNS server does not refresh the resource record for the duration of non-refresh interval. It can refresh the record before non-refresh interval if any update, such as the IP address of the host changes and it resets the time stamp accordingly. The DNS server refreshes the record after the non-refresh interval expires. During and after the refresh interval if any update comes it accepts and refresh the record. The server examines the subsequent scavenging and each record is compared to server time to determine whether the record should be removed and this is done by using scavenging formula.

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Job Interview Tips - What Not to Say in a Job Interview

 

Interviewing for any job can create stress, and for some, can result in a lack of good judgment when it comes to what to talk about. Many interviewees with good intentions, can end up saying things that are inappropriate or inaccurate, which ultimately costs them the job.  

• Do not speak negatively about your past employer or organisation. If asked why you are leaving or why you left, simply say that you are looking for a new opportunity. Talking badly about your former boss, company or co-workers will come across as negative.
• If you are uncomfortable about providing private and /or sensitive information about your current employer (such as financials), avoid a negative response by saying “I’m not sure my company would like me to disclose that information". Ideally, if talking about financials, you can use a range instead of exact amounts. For example, company turnover being $35Mil, then you can provide a range of "$30Mil to $40Mil". This is a more helpful strategy.
  
• Avoid discussing salary until the interviewer brings it up. Typically, this will come up after you have been offered the position, or at the end of the interview. Immediately asking “How much will I get paid?” or asking "When is the next pay rise" could have the interviewer believing that money is a number one factor.


• Do not say anything that is not true about your past work history. The interviewer will most likely cross reference your past jobs,so you will eventually get caught out and lose the job. Always be honest about your experiences, history and abilities. If the interviewer asks why you were fired from a job, be forthcoming but explain how you have learned from the mistake. Never lie and say that you left of your own accord, if indeed you were released.


• Do not interrupt the interviewer. Always let them lead the conversation and set the pace of  the interview. If you interrupt or try to lead, you will come across as pushy and someone who doesn't demonstrate good listening skills. Stop yourself from over talking!


•  In an interview, you want to remain professional, yet friendly. But don't get too friendly and share too many details. Keep your answers simple, concise and to the point so that you avoid babbling on unnecessarily and giving away personal information. Always remember, this is an interview!

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Job interview - Questions to Ask

It's important to ask questions in an interview. These should be questions to clarify job specifics through to key points of interest which will enable you to determine whether this is the right job, employer and culture fit for you.

• What are the most important skills and characteristics your
• What made you decide to join the company? (providing they don't own the business!)
• What has been the pattern of growth for the company over the past 5 years
• What is the future growth plan of the company?
• Why is this job open?
• How many people held this position over the recent years?
• How does this position fit into the overall organisation?
• Who will I be reporting to
• Where is the job located by way of company structure?
• What type of training is required for this position? How long is the training period?
• What other training opportunities are provided?
• Where are the greatest opportunities for growth within the company?
• Who are the company's major competitors?
• Who are your major customers? Are they mostly local, regional or global
• What will my priorities be? What will be my first assignment?
• What issues/challenges am I likely to face when I first take on the role?

Remember: write some questions down before interview and during the interview. Don't try to leave everything to memory. It's also down to you to have the confidence to ask the questions, and to ask question that you feel will be relevant in helping you make your decision. It's a two way process where both you and the interviewer need to know more.

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ATO Scam Alert

 🚨 SCAM ALERT 🚨 Be on the lookout for a new phone #scam claiming your #tax file number (TFN) has been suspended!

Recorded phone calls claiming to be from the #ATO and other government agencies are trying to trick people into providing personal information. These scammers will tell you there’s a legal case against you, and if you don’t follow instructions and provide the information requested, you’ll be arrested.

⚠️ Don’t follow the prompts, and don’t provide the information requested. We will never send unsolicited pre-recorded messages to your phone, or threaten you with immediate arrest. If you’re ever unsure whether an #ATO interaction is genuine, hang up and phone our scam hotline on 1800 008 540. Warn your family and friends to stay alert and visit scam alerts page to learn more:

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Phishing and spear-phishing method of stealing confidential information

 In the recent Stay Smart Online, Alert email advise that there is a significant increase in the past few months of COVID themed phishing scams, using all sorts of lures to try and trick people into handing over personal details.

#Phishing and spear-phishing is a method of stealing confidential information by sending fraudulent messages to a victim, through email or message platforms. They remain among the MOST common method used by malicious #cyber actors to target Australians.

Since the #pandemic's outbreak, the Government’s #Scamwatch has received over 3,060 coronaviruses themed scam reports with over $1,371,000 in reported losses.

#Phishing campaigns can be sent via email, SMS, social media, instant messenger or a phone call. They can look extremely convincing, often imitating legitimate messages from trusted senders in government or business.

See attached are an example of #scam #email that I usually get in my (test) mailbox. Look at the subjects all trying to attract you in a way to click a link or provide details. Especially now Corona and Tax return season they are more active than before.

Hope this helps to Stay safe and on alert don't lose your money or info to the scammers.

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Beware of COVID style scam

 Beware of COVID style scam. This is phone scam but COVID email, app, and web scam also present which I have shared previously

It goes like this
Scammer: Good morning, According to our system, you are likely to have been in close proximity to someone who has tested positive for COVID-19. This means that you now need to self-isolate for 14 days and take a COVID-19 test.

'OK. Can you tell me who that person was?'

Scam : 'I'm not able to tell you that. That is confidential information.

Right. Um... so ....

Scam : But you do need to be tested within the next 72 hours. So can I just get the best mailing address so that we can send a kit to you?'

Ok (gives address)

Scam : Thank you - and I just need to take a payment card so that we can finalize this and send the kit to you.'

Sorry - a payment card? I thought this was all free?' - RED ALART here people

Scam : No - I'm afraid not. There is a one-off fee of $50 for the kit and test results. Could you read off the long card number for me, please, when you're ready.'

No - that's not right

Scam: I'm afraid it is. Can you give me the card number please - this is very important, and there are penalties for not complying.'

You should Put the phone down.

This is how #scammers work. And vulnerable people will fall for it.

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Group Policy Interview Questions and Answers for Windows Administrator

What are group policies?
Group policies specify how programs, network resources, and the operating system work for users and computers in an organization. They are collections of user and computer configuration settings that are applied on the users and computers (not on groups). For better administration of group policies in the Windows environment, the group policy objects (GPOs) are used.

What is GPO?
Group policy object (GPO) is a collection of group policy settings. It can be created using a Windows utility known as the Group Policy snap-in. GPO affects the user and computer accounts located in sites, domains, and organizational units (OUs). The Windows 2000/2003 operating systems support two types of GPOs, local and non-local (Active Directory-based) GPOs.

What is Local GPOs/policy?
Local GPOs are used to control policies on a local server running Windows 2000/2003 Server. On each Windows  server, a local GPO is stored. The local GPO affects only the computer on which it is stored. By default, only Security Settings nodes are configured. The rest of the settings are either disabled or not enabled. The local GPO is stored in the %systemroot%SYSTEM32GROUPPOLICY folder.

What is Non-local Policy?
Non-local GPOs are used to control policies on an Active Directory-based network. A Windows  server needs to be configured as a domain controller on the network to use a non-local GPO. The non-local GPOs must be linked to a site, domain, or organizational unit (OU) to apply group policies to the user or computer objects. The non-local GPOs are stored in %systemroot%SYSVOLPOLICIESADM, where is the GPO’s globally unique identifier. Two non-local GPOs are created by default when the Active Directory is installed:
1. Default Domain Policy: This GPO is linked to the domain and it affects all users and computers in the domain.
2. Default Domain Controllers Policy: This GPO is linked to the Domain Controllers OU and it affects all domain controllers placed in this OU.
Multiple GPOs

GPO Apply order
When multiple group policy objects are assigned, the group policies are applied in the following order:
• The local group policy object is applied first
• Then, the group policy objects linked to sites are applied
If multiple GPOs exist for a site, they are applied in the order specified by an administrator
• GPOs linked to the domains are applied in the specified order
• Finally, GPOs linked to OUs are applied
The OU group policy objects are set from the largest to the smallest organizational unit, i.e., first the parent OU and then the child OU.
By default, a policy applied later overwrites a policy that was applied earlier. Hence, the settings in a child OU can override the settings in the parent OU
Group policy settings are cumulative if they are compatible with each other. In case they conflict with each other, the GPO processed later takes precedence.

What is No Override? Block Policy Inheritance?
The following are the exceptions with regard to the above-mentioned settings:
 No Override:
Any GPO can be set to No Override. If the No Override configuration is set to a GPO, no policy configured in the GPO can be overridden. If more than one GPO has been set to No Override, then the one that is the highest in the Active Directory hierarchy takes precedence
Block Policy Inheritance:
The Block Policy Inheritance option can be applied to the site, domain, or OU. It deflects all group policy settings that reach the site, domain, or OU from the object higher in the hierarchy. However, the GPOs configured with the No Override option are always applied
What is Loopback policy?

Is group policy from Parent Domain cab be inherited to child Domain?
Group Policy Inheritance
The group policies are inherited from parent to child within a domain. They are not inherited from parent domain to child domain

Following are the rules regarding group policy inheritance:
A policy setting is configured (Enabled or Disabled) for a parent OU, and the same policy setting is not configured for its child OUs. The child OUs inherit the parent’s policy
A policy setting is configured (Enabled or Disabled) for a parent OU, and the same policy setting is configured for its child OUs. The child OUs settings override the settings inherited from the parent’s OU
If any policy is not configured, no inheritance takes place
Compatible policy settings configured at the parent and child OUs are accumulated
Incompatible policy settings from the parent OU are not inherited

What is security filtering? Filtering Scope of GPOs
Although GPOs are linked to the site, domain, or OUs, and they cannot be linked to the security groups directly, applying permissions to the GPO can filter its scope. The policies in a non-local GPO apply only to users who have the Read and Apply Group Policy permissions set to Allow
By specifying appropriate permissions to the security groups, the administrators can filter a GPO’s scope for the computers and users

What Tools used to edit the Group policy?
GPMC and GPedit
How to check applied policy details from Client or server?
RSOP.msc (only works windows 2003 and above)
GPRESULT /v

What is .adm file?
Administrative Template are  required because Microsoft did not include all Registry settings in the default Group Policy, if you want to add more customized setting to existing policy then .ADM file can be created and imported to get the necessary setting

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Commonwealth Bank SCAM Alert

#SCAM ALERT:

hashtag

Watch out for this #phishing scam from 'Commbonk'. The scam starts as an email using various display names, each containing the word ‘CommBank’. Unsuspecting recipients who click on the link to view ‘transaction details’ are each led to a different page which redirects to a page using the domain 'commbonk'. According the security company, MailGuard, this is a phishing page masquerading as a fake Commonwealth Bank sign-in page. Don't click on the link and delete email immediately. . The scam starts as an email using various display names, each containing the word ‘CommBank’. Unsuspecting recipients who click on the link to view ‘transaction details’ are each led to a different page which redirects to a page using the domain 'commbonk'. According the security company, MailGuard, this is a phishing page masquerading as a fake Commonwealth Bank sign-in page. Don't click on the link and delete email immediately. .

• use of a major brand name to inspire false trust; the usage of the supposed ‘Commonwealth’ display name boosts the email's credibility,

• inclusion of ‘Helplines’ typically expected of a well-established bank such as bank support numbers for local and overseas locations in the email & support links in the phishing page and,

• false urgency; a subject line such as ‘Action Required’ and a signature supposedly from 'Commonwealth Bank of Australia Fraud Security Support' creates a sense of panic and anxiety.

Commonwealth Bank impersonated in phishing scam; email asks users to confirm card ‘activity’

The hallmark of this scam lies in its ability to trick users by ironically using a security alert. Verifying irregular transaction activity is a common trait of well-established banks like Commonwealth and it’s this focus on security that cybercriminals behind this scam leverage on. Here are some of the specific techniques they’ve incorporated to trick recipients:

Despite these techniques to fool users into thinking the email is authentic, eagle-eyed recipients will spot red flags that point to its illegitimacy, with the biggest being the fact that the link doesn't actually point to Commonwealth Bank. Besides this, the email also contains spacing errors and grammatical mistakes like ‘are all transactions listed above clear for you?’.

This is another reminder for those who utilise online banking, to pay close attention to the emails they receive from their banks. To best protect yourself, it is imperative that you do not click any link contained within an email, especially if it does not address you by name (as in the scam above). It is best practice to type the website URL into your browser or use the official banking app in this instance.

As banks have been a major target for scammers, they have also been working hard to distinguish their legitimate correspondence from the ‘fakes’ and educating their customers on best security practices. This is also why any legitimate correspondence from your bank won't have links to their website. Banks will instead ask you to manually enter it into your internet browser. Also, if you are ever unsure if it is your bank genuinely trying to reach you, simply contact them directly to confirm.

Further information at - https://www.mailguard.com.au/blog/commonwealth-bank-impersonated-in-phishing-scam-email-asks-users-to-confirm-card-activity

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