Bulk reverse DNS

The Bulk changes card of the Reverse DNS page changes the PTR of several addresses at once: you upload a JSON, CSV or text file (or paste its content), YorkHost checks it line by line, then applies it.

The easiest way: export the current list, edit it, upload it again.

1. Export the current list

In Manage → DNS & rDNS → Reverse DNS, Bulk changes card, click Export CSV or Export JSON. The export covers the IP addresses shown: all your IP addresses, or those of the selected service.

CSV export (the comment line is written in the language of your client area):

# YorkHost reverse DNS: edit and upload this file again. Empty name, "default" or "reset" = default value. "#" lines are ignored.
ip,hostname
192.0.2.10,mail.example.com
192.0.2.11,web1.example.com
#192.0.2.12,

• IP addresses without a published PTR are commented out (#192.0.2.12,): remove the # and add the name to set them.
• IP addresses whose reverse zone is not managed by YorkHost are not listed (they cannot be changed here).

JSON export: an {"ip": "name"} object; IP addresses without a published PTR are left out.

{
  "192.0.2.10": "mail.example.com",
  "192.0.2.11": "web1.example.com"
}

The exported file can be uploaded as is: it changes nothing.

2. Edit the file

Accepted formats (detected automatically):

Lines: one address per line, ip,name, ip;name, tab or spaces. The ip,hostname header line is optional; blank lines and # comments are ignored.

ip,hostname
192.0.2.10,mail.example.com
192.0.2.11;web1.example.com
2001:db8::10 v6.example.com
192.0.2.13,default

JSON object:

{"192.0.2.10": "mail.example.com", "192.0.2.13": ""}

JSON array (ptr or rdns accepted instead of hostname):

[
  {"ip": "192.0.2.10", "hostname": "mail.example.com"},
  {"ip": "2001:db8::10", "ptr": "v6.example.com"}
]

To go back to the default name provided by YorkHost: empty name, default or reset.

Each name follows the same rules as a single change: fully qualified host name, and preferably forward-confirmed for a mail server.

3. Check, then apply

1. Choose the file (drop it on the card or choose a file), or paste its content in Or paste the content.
2. The Check only (do not change anything) box is ticked by default: leave it ticked and click Send. Nothing is changed; you get a line-by-line report.
3. Fix the lines in error if needed, then send the file again with "Check only" unticked to apply the changes.

For each line, the report shows Line, IP address, Requested name, Result and Warning.

Result	Meaning
To change	(check) The line is valid and would be applied.
Changed	The PTR was changed.
Unchanged	The PTR already has this value: nothing is written.
Error	The line is refused (the message explains why).
Not applied	The line was valid but not applied (hourly limit, see below).

Limits and rules

• File of 256 KB max.
• 512 addresses max per upload. Beyond that, nothing is changed: split the file.
• UTF-8 text (UTF-8 BOM and Windows line endings are accepted). A binary or unreadable file is refused as a whole.
• An address listed more than once: none of its lines is applied.
• An IP address that does not belong to your account, or whose reverse zone is not managed by YorkHost, is a line error; the other lines are processed.
• Invalid JSON is read again as lines: each unreadable line then becomes an error.

Hourly limit: all or nothing

DNS and rDNS changes are limited per hour (client area and API together). If the number of changes left for the current hour is not enough for the whole batch, nothing is changed: "This batch needs … change(s) and … remain for this hour: none was applied. Send fewer lines or try again later." The lines are then marked Not applied.

Checking only is still possible when the limit is reached. Only the lines that actually change something are counted (plus one action for the batch itself): Unchanged lines cost nothing.

Through the API or MCP

The same processing is available through the API (POST /client/v1/rdns/bulk) and the rdns_bulk MCP tool, with a check mode (check_only): see DNS and rDNS through the API and MCP.