Sathiya's Blog

How to avoid your email going to spam

Everyone raising question that ‘How to avoid your email going to span? Getting unwanted junk of mail flooding into inbox on daily basis. Yes, email filtering mandatory in exchange server including public service as Gmail, Outlook, Yahoo or any.

SPF, DKIM and DMARC playing big role to tag your email healthy and secure to receivers mail servers. Beside check email score to make necessary changes with domain DNS.

To check email rating with Mail-Tester.com or IsNotSpam.com, based on the result fix major issues and maintain score 8+ to avoid going spam. Also validate blacklist IP and domain on MxToolbox.com.

SPF – Sender Policy Framework

Select your domain
Navigate/click DNS management
Click ‘Add’ new record based on hosting provider console
In dropdown pick record type as TXT record
Create a new TXT records
- Host: The domain or subdomain for the SPF record. Feed your root domain, enter @ as in Host field.
- TXT Value: The SPF rule to be applied. For example, enter v=spf1 mx -all to indicate emails are allowed from your mail server and no others. Check out more rule on SPF record syntax.
- TTL: Keep default setting as 1 hour
Save changes and allow minimum 24hr to reflect/publish them.

DKIM

log in to SendGrid‘ dashboard;
Navigate Settings/Sender Authentication -> Authenticate Your Domain, choose your DNS host and click the Next button.
Select appropriate DNS host system
Optional: “brand the links for this domain?” Subdomain can be added to authenticate.

Enter domain name which required to authenticate

Select below field under ‘Advanced settings’
- Use automated security
- Use a custom DKIM selector – domain short identity

Add generated CNAME into domain DNS section
Check record in DKIM checks

DMARC

Add SPF and DKIM record before DMARC, login to dmarcly.com to complete the process. Follow the process on create record

September 6, 2020

Export Json to Csv in PowerShell

In Big-data era, the data are stored in flat files which is supporting wider range of technology and systems. Json is serialized data to feeds into multiple development language and automation scripts in devOps system. Export Json to Csv would common question whoever doing data across platform, here are the simple script to claim your times.

Despite data needs to insert into MSSQL in Azure DB so converting to Csv.

Example 01

If the Json has a header and value that required to -Join. Below Servers json data file has columns and values.

{
        “servers”: {
                “columns”: [“ID”, “V_NAME”, “DATE”, “TIME”],
                “values”: [
                        [“SRVIIS01, “server1”, “city123”, “02\/14\/2020”, “15:34:15”],
                        [“SRVSP01”, “server2”, “cit3”, “02\/14\/2020”, “12:58:32”]
                ]
        }
}

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{

“servers”: {

“columns”: [“ID”, “V_NAME”, “DATE”, “TIME”],

“values”: [

[“SRVIIS01, “server1“, “city123“, “02\/14\/2020“, “15:34:15“],

[“SRVSP01“, “server2“, “cit3“, “02\/14\/2020“, “12:58:32“]

]

}

PowerShell to ConvertFrom-Csv

$file = “C:\Users\winadmin\Downloads\custom_data\server_data.json”
$json = ConvertFrom-JSON (Get-Content $file -Raw)
$json.servers.values | ForEach-Object {
    # If json has header and content then used below -join to ConvertFrom-CSV with -Header values
    $_ -join ‘,’ | ConvertFrom-Csv -Header $json.servers.columns | Export-Csv -path C:\Users\winadmin\Downloads\custom_data\server_data.csv -NoTypeInformation -Append
}

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$file = “C:\Users\winadmin\Downloads\custom_data\server_data.json”

$json = ConvertFrom–JSON (Get–Content $file –Raw)

$json.servers.values | ForEach–Object {

# If json has header and content then used below -join to ConvertFrom-CSV with -Header values

$_ –join ‘,’ | ConvertFrom–Csv –Header $json.servers.columns | Export–Csv –path C:\Users\winadmin\Downloads\custom_data\server_data.csv –NoTypeInformation –Append

}

Example 02

Play with Export-Csv to save the file

{
	“servers”: [
		{
			“ID”: “SRVIIS01”,
			“V_NAME”: “”,
			“DATE”: “02\/14\/2020”,
			“TIME”: “15:34:15”,
		},
		{
			“ID”: “SRVSP01”,
			“V_NAME”: “”,
			“DATE”: “02\/14\/2020”,
			“TIME”: “20:34:15”,
		}
	]
}

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{

“servers”: [

{

“ID”: “SRVIIS01”,

“V_NAME”: “”,

“DATE”: “02\/14\/2020”,

“TIME”: “15:34:15”,

},

{

“ID”: “SRVSP01”,

“V_NAME”: “”,

“DATE”: “02\/14\/2020”,

“TIME”: “20:34:15”,

}

]

}

PowerShell – Export list value directly to csv with out join comment.

$file = “C:\Users\winadmin\Downloads\custom_data\server_data.json”
$json = ConvertFrom-JSON (Get-Content $file -Raw)
$json.servers.values | ForEach-Object {
    # If json has header and content then used below -join to ConvertFrom-CSV with -Header values
    $_ | Export-Csv <span class=”hljs-parameter”>-UseQuotes</span> AsNeeded -path C:\Users\winadmin\Downloads\custom_data\server_data.csv -NoTypeInformation -Append
}

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$file = “C:\Users\winadmin\Downloads\custom_data\server_data.json”

$json = ConvertFrom–JSON (Get–Content $file –Raw)

$json.servers.values | ForEach–Object {

# If json has header and content then used below -join to ConvertFrom-CSV with -Header values

$_ | Export–Csv <span class=“hljs-parameter”>–UseQuotes</span> AsNeeded –path C:\Users\winadmin\Downloads\custom_data\server_data.csv –NoTypeInformation –Append

}

Export-Csv -UseQuotes AsNeeded work in PowerShell v6 and higher. So download and install latest version from MS git release.

May 3, 2020

Replace permission command line

Migration is always popping an issues to bring the service online. Moreover folder permission playing a big role in all scenario; Apparently spent lot of time to fix data migration issues from Windows 2008 server to Windows 2012 server. So replace permission required to complete the migration.

Scenario:

Application data needs to be migrated (folders & files) from Windows 2008 server [SERVER2K8] to Windows 2012 server [SERVER2K12]. Consider the folder permission as old server local security groups named ‘SERVER2K8\App Admin’, however copying the data using robocopy with permissions using below scripts

Copy folder with privileges

robocopy \\SERVER2K8\Data \\SERVER2K12\Data /E /copy:DAS

1	robocopy \\SERVER2K8\Data \\SERVER2K12\Data /E /copy:DAS

save and restore folder permission with substitute, deleted or unavailable user’s SID will not work.

icacls /restore /substitute [oldAccount] [newAccount]

1	icacls /restore /substitute [oldAccount] [newAccount]

Hence, ‘SubInACL’ script with replace parameter helps to fix SID mapping to resolve broken rights, download and install Windows Resource Kits. Similarly Applicable for domain account and group migrations.

Replace permission for broken SID with new user/groups ID

SubInACL.exe /subdirec \\SERVER2K12\Data /replace=S-1-5-21-xxxxx-xxxxx-xxxxx-xxx=S-1-5-21-yyyyy-yyyyy-yyyyy-yyy

1	SubInACL.exe /subdirec \\SERVER2K12\Data /replace=S–1–5–21–xxxxx–xxxxx–xxxxx–xxx=S–1–5–21–yyyyy–yyyyy–yyyyy–yyy

March 15, 2020

Remove Blacklist Domain SPAMRATS

RATS Dyna block list is common to avoid Trojan and bots sending mail to recipients. SPAMRATS detect unhealthy and invalid rDNS records entries in server. Remove Blacklist from span filter domain, add PTR record in DNS server. In case of on-perm outgoing mail apparently get the IP from ISP.

In my scenario, mail service has hosted in O365 and multiple web application pointing to same IP. Due to this RATS Dyna marked as blacklist http://www.spamrats.com/bl?[xx.xx.xx.xx]. Whereas domain purchased in GoDaddy.com service provider. rDNS supposed to be added in service provider end refer https://in.godaddy.com/help/add-my-own-host-names-as-nameservers-12320 where we could archive and fix an issues.

Adding ‘Host name’ under advanced feature to fix rDNS issues. Here added ‘mail.sathiya.io’ to 10.xx.xx.xx; Make sure to validate an entry with mxtoolbox.com or dnschecker.org

February 25, 2020

Torrent Downloader for Mac Catalina

I have been updated Catalina recently after all most of the application and custom configuration are not functioning. The build macOS 10.15.1 Catalina more secure than previous release. Also system ‘root’ been default as read only (Writeable: No) state. Read more about Catalina release note

Due to security reason uTorrent, BitTorrent client applications stopped working even new release either. In that case Vuze Download could fix them. SUDO access required to install the package so use terminal as sudo to make it work.

Error message: “You must be logged in as root when installing this program”.

For example running Vuze downloader use below comment

sudo /Volumes/Storage/Downloads/Vuze\ Installer.app/Contents/MacOS/JavaApplicationStub

1	sudo /Volumes/Storage/Downloads/Vuze\ Installer.app/Contents/MacOS/JavaApplicationStub

Warning: Make sure the package doesn’t has Malware or Malicious codes

November 23, 2019

Unexpectedly deleted search index entries

SharePoint 2019 security CVE-2019-1330 patch has been released in October’19. The patch causing search indexes the crawl of content that has many links fails because of the maximum allowable links exceeds. So multiple fails, the search index entries for the content are deleted unexpectedly.

So ContentPIMaxNumLinks properties should be updated accordingly with below SharePoint 2019 Management shell script;

$ssa = Get-SPEnterpriseSearchServiceApplication
$ssa.SetProperty(“ContentPIMaxNumLinks”, 10000)
$ssa.Update()

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$ssa = Get–SPEnterpriseSearchServiceApplication

$ssa.SetProperty(“ContentPIMaxNumLinks”, 10000)

$ssa.Update()

Check out historical security and cumulative updates more in!

October 19, 2019

HTTPS Rewrite Linux/Hosting .htaccess

Discussed HTTP to HTTPS rewrite rule for windows platform IIS on previous post. If the web server as linux based environment that can be archived and play with .htaccess file.

.htaccess file has always in hidden attribute so edit the file with vi editor

sudo vi .htaccess

1	sudo vi .htaccess

Add the below code of mod_rewrite.c module to make http to https redirection.

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{HTTPS} !=on
RewriteCond %{HTTP_HOST} ^(www\.)?sathiya.io [NC]
RewriteRule (.*) https://sathiya.io/$1 [L,R=301,QSA]
#If ‘www’ is required then enable below rule instead of above one
#RewriteRule (.*) https://www.sathiya.io/$1 [L,R=301,QSA]
</IfModule>

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RewriteEngine On

RewriteBase /

RewriteCond %{HTTPS} !=on

RewriteCond %{HTTP_HOST} ^(www\.)?sathiya.io [NC]

RewriteRule (.*) https://sathiya.io/$1 [L,R=301,QSA]

#If ‘www’ is required then enable below rule instead of above one

#RewriteRule (.*) https://www.sathiya.io/$1 [L,R=301,QSA]

</IfModule>

Cheers!

Suggestion: HTTP to HTTPS rewrite rule (IIS)

November 15, 2018

HTTP to HTTPS rewrite rule

Typically http to https configuration would be common as the canonical name redirect either http:// or http://www to https. This may be the site requirement as https:// or https://www

In our scenario, rewrite rule could be managed to https://www with canonical name.

Whenever client end entering the URL as http://www.sathiya.io or http://sathiya.io would be automatically redirect to https://www.sathiya.io site.

More about rewrite rule on Microsoft article

<rewrite>
    <rules>
        <rule name=”Canonical Host Name (HTTP)” stopProcessing=”true”>
        <match url=”(.*)” />
        <conditions logicalGrouping=”MatchAll”>
            <add input=”{HTTPS}” pattern=”OFF” />
            <add input=”{HTTP_HOST}” pattern=”(?=^sathiya\.io)(?=^(.(?!\/ezine\/))*$)” />
        </conditions>
<action type=”Redirect” url=”http://www.sathiya.io/{R:1}” redirectType=”Permanent” />
</rule>

<rule name=”Canonical Host Name (HTTPS) www” stopProcessing=”true”>
<match url=”(.*)” />
<conditions logicalGrouping=”MatchAll”>
<add input=”{HTTPS}” pattern=”OFF” />
<add input=”{HTTP_HOST}” pattern=”(?=^www.sathiya\.io)(?=^(.(?!\/ezine\/))*$)” />
</conditions>
<action type=”Redirect” url=”https://www.sathiya.io/{R:1}” redirectType=”Permanent” />
</rule>

<rule name=”Canonical Host Name (HTTPS)” stopProcessing=”true”>
<match url=”(.*)” />
<conditions logicalGrouping=”MatchAll”>
<add input=”{HTTPS}” pattern=”ON” />
<add input=”{HTTP_HOST}” pattern=”(?=^sathiya\.io)(?=^(.(?!\/ezine\/))*$)” />
</conditions>
<action type=”Redirect” url=”https://www.sathiya.io/{R:1}” redirectType=”Permanent” />
</rule>
</rules>
</rewrite>

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<rules>

</conditions>

</rule>

</conditions>

</rule>

</conditions>

</rule>

</rules>

</rewrite>

Cheers!

October 24, 2018

SharePoint Server 2019 Public Preview

As expected Microsoft introduced SharePoint server 2019 product in May 2018 SharePoint conference. The product has more refined feature in terms of user experience, development stuff, security concerns and scalable with Hybrid collaboration environments

Now, public preview available to experience the complete features of next milestone.

SharePoint Server 2019 Public Preview

Product	Build Number	Package Name	Download/Release CU	Release Date
SharePiont 2019	16.0.10711.37301	Public preview	Download	2018 July 24

Features

Find the major noticeable features;

Modern user experience based on online product
Content across browser and devices
Robust scalability, security and compliance capabilities

Previous production has a limitation in larger file, character restrictions, files/folder names those are improved in 2019

File can be upload upto 15GB
URL length has been Increases from 260 Unicode code units to 400.

Tip: SharePoint 2019 complete features, checkout white paper.

Cheers!

September 8, 2018

Validate Active Directory (AD) Credentials

To configuring service account for the application after creating generated password causing issue many times, needs to validate active directory (AD) credentials before configuring it. Because enterprise level policy would disable service account with bad password attempts. The PowerShell script helps to validate efficiently.

<#
.DESCRIPTION
    Validate AD Account credential
.NOTES
    Author: Sathiya.io
#>
function Man-TestADUserAuth {
$cre = Get-Credential -Credential $null
if((new-object directoryservices.directoryentry “”,$cre.UserName,$cre.GetNetworkCredential().Password).psbase.name -ne $null) {
    Write-Host “Password is valid!” -ForegroundColor Green
}
else {
    Write-Host “Sorry! Either user name or password wrong!” -ForegroundColor Red -BackgroundColor Yellow
}
}
Man-TestADUserAuth

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<#

.DESCRIPTION

Validate AD Account credential

.NOTES

Author: Sathiya.io

#>

function Man–TestADUserAuth {

$cre = Get–Credential –Credential $null

if((new–object directoryservices.directoryentry “”,$cre.UserName,$cre.GetNetworkCredential().Password).psbase.name –ne $null) {

Write–Host “Password is valid!” –ForegroundColor Green

}

else {

Write–Host “Sorry! Either user name or password wrong!” –ForegroundColor Red –BackgroundColor Yellow

}

Man–TestADUserAuth

Scripts makes perfect, Cheers!

July 1, 2018