Questions tagged [rfc]
A Request for Comments (RFC) is a publication of the Internet Engineering Task Force (IETF) and the Internet Society, the principal technical development and standards-setting bodies for the Internet.
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DNS using CNAMEs breaks MX records?
We are trying to move all our websites we host to CNAMES as we are planning on moving servers in the new year and would like the ability to move some clients to one server and other clients somewhere ...
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Which RFCs should be cited as internet standards?
It's extremely common for RFCs to be cited in support of opinions (including Serverfault Q&A's), but the average IT employee has a very poor understanding in regards to which RFCs define standards ...
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SMTP allows for multiple FROM addresses in the RFC. Was this ever useful, why does this exist?
SMTP allows for multiple FROM addresses on the body (not the envelope) according to the RFCs.
Has this feature ever been used for a legitimate purpose?
Is it safe to discard messages that have ...
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Legitimate reasons SMTP “MAIL FROM:” will not match “From:” Header in DATA
Is there ever a legitimate reason for the SMTP “MAIL FROM:” field to not match the “From:” field in the DATA section of a message, besides mailing lists?
From https://stackoverflow.com/questions/...
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Where is the documentation that states TCP and UDP source port should be over 1024 and random?
I am having a hard time to find where it is documented that the source port should be random and in the range 1024-65535.
In which RFC is this documented?
Edit:
First reference for privileged ports ...
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What's the maximum URL length in Tomcat?
And is it configurable? Can I set up Tomcat so that a URL with, say, 200K of query params goes through successfully to the contained servlet?
Yes, I know one should use POST when you have lots of ...
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How does the DNS protocol switch from UDP to TCP?
Before anyone asks: I've seen When do DNS queries use TCP instead of UDP? and it doesn't answer my question.
All I keep hearing is "if the answer is too long, DNS will use TCP". This does not explain ...
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What's the point of repeating an email address in "The Envelope" and the "The Header"?
I learned that both the FROM address and the TO address is repeated in a hidden element called the "envelope", and then repeated again in the "body".
Question
Why isn't the envelope data copied into ...
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What is the point of the zones.rfc1918 file for Bind9?
Using an Ubuntu 10.04 LTS server in a standalone environment and trying to use views to serve two different subnets of clients. Getting errors regarding the zones.rfc1918 file, so I'd like to know ...
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RFC that requires DNS servers to respond to unknown domain requests
My domain registrar and DNS provide currently ignores DNS requests to unknown domains. By ignore I mean black-holes and never responds which causes my DNS clients and resolver libraries to retry, ...
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What to do if one doesn't want to receive email bounces?
Background—the standards
RFC 5321 §4.5.5 states:
All other types of messages (i.e., any message which is not required
by a Standards-Track RFC to have a null reverse-path) SHOULD be sent
with a valid,...
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Hotmail wants me to modify my SPF record
This is my current SPF record. It works well with gmail and yahoo but hotmail was ignoring. So i used their submit system and now they replied me with the text below.
This is my current spf
v=spf1 a ...
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How to configure bind for a private subdomain?
I am attempting to define a subdomain for a private network (RFC1918) behind a NAT firewall; let's call it priv.example.com. Normally, and from what I can gather on various websites, this could be ...
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DHCP renewal can't go through because DHCP server is down
To my experience, if a DHCP client tries to renew its lease, but the DHCP server is down, and after the lease time is over, there are two possible scenarios:
The client keeps the IP
The client goes ...
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