SendGrid Tracking Subdomain

How sendgrid generated this tracking url u8345.postmymeds.co.uk
Where I will found this subdomain

SendGrid uses tracking subdomains to track email opens and clicks. The subdomain `u8345.postmymeds.co.uk` is likely a **click tracking subdomain** generated by SendGrid for your email campaign. This subdomain is created based on your domain settings in SendGrid and the type of tracking you have enabled (e.g., click tracking, open tracking, etc.).

### How SendGrid Generates This URL
1. **Domain Authentication**: When you authenticate a domain with SendGrid, you typically configure DNS records (CNAMEs) pointing to SendGrid's servers. For example:
– `u8345.postmymeds.co.uk` might resolve to something like `sendgrid.net`.

2. **Tracking**: If click tracking is enabled in your SendGrid account, links in your email will be rewritten to use this tracking subdomain. When a recipient clicks a link, the request first goes to the tracking subdomain (e.g., `u8345.postmymeds.co.uk`), which records the click before redirecting the user to the actual destination.

### Where to Find This Subdomain
1. **DNS Settings**: Check your DNS records for `postmymeds.co.uk`. Look for CNAME records related to `u8345` or other subdomains pointing to SendGrid (`sendgrid.net`).

2. **SendGrid Account**:
– Go to **Settings > Sender Authentication** in your SendGrid dashboard.
– Look for the domain you authenticated.
– The tracking subdomain (`u8345.postmymeds.co.uk`) should be listed as part of your domain setup.

3. **Email Headers**:
– If you received an email that uses this tracking subdomain, examine the email headers. Look for `X-SG-EID` or similar SendGrid-specific tracking information.

4. **SendGrid Link Settings**:
– In your SendGrid account, navigate to **Settings > Tracking**.
– Click on **Click Tracking** to verify the domain/subdomain being used for tracking.

If you don't see this subdomain in your DNS records, it may have been misconfigured or auto-assigned by SendGrid temporarily. Double-check your SendGrid settings and re-authenticate the domain if necessary.

Suddenly it removes https to http

If your SendGrid tracking URLs are suddenly switching from **HTTPS** to **HTTP**, this usually indicates a misconfiguration in your domain or SSL setup for the tracking subdomain. Here’s how to troubleshoot and fix the issue:

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### Possible Causes and Fixes

#### 1. **SSL Not Configured Properly for the Subdomain**
– SendGrid requires you to authenticate your domain and configure DNS records. If HTTPS is not working, the SSL/TLS certificate might not be properly applied to the tracking subdomain (`u8345.postmymeds.co.uk`).
– **Fix**:
1. Verify the DNS settings for your subdomain in your domain registrar. Ensure the CNAME record for `u8345` points to `sendgrid.net`.
2. Re-authenticate your domain in SendGrid to ensure proper SSL/TLS is applied:
– Go to **Settings > Sender Authentication** in SendGrid.
– Select your domain and re-authenticate if necessary.
3. Check with your domain host that SSL is enabled and properly configured for `u8345.postmymeds.co.uk`.

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#### 2. **Click Tracking Settings in SendGrid**
– SendGrid might fall back to HTTP if the HTTPS configuration is incomplete or not enforced.
– **Fix**:
1. Log in to your SendGrid account.
2. Navigate to **Settings > Tracking > Click Tracking**.
3. Ensure the option for **Secure Click Tracking (HTTPS)** is enabled.

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#### 3. **DNS Propagation Delay**
– If you recently updated your DNS settings to point the subdomain to SendGrid, there might be a propagation delay, leading to fallback to HTTP.
– **Fix**:
– Wait 24–48 hours for DNS changes to propagate globally.
– Use tools like [WhatsMyDNS](https://www.whatsmydns.net/) to verify the DNS propagation for the tracking subdomain.

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#### 4. **SendGrid Platform Issue**
– Sometimes, SendGrid may have an issue with their SSL setup for your domain.
– **Fix**:
1. Contact SendGrid support and report the issue.
2. Request them to check the SSL/TLS configuration for your domain.

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#### 5. **Email Client Issue**
– In rare cases, the email client may incorrectly strip HTTPS from links due to its handling of URLs.
– **Fix**:
– Test the same email on multiple email clients (e.g., Gmail, Outlook, etc.) and verify if the issue persists.

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### Verifying the Issue
1. Use an online SSL checker (e.g., [SSL Labs](https://www.ssllabs.com/ssltest/)) to check the SSL status of `u8345.postmymeds.co.uk`.
2. Inspect the email's HTML content to see if the URLs are being generated as HTTP or HTTPS.

By addressing the root cause—whether it's DNS configuration, SendGrid settings, or SSL issues—you should be able to ensure your tracking links consistently use HTTPS.