RFC relevance of february

As per Relevance of the word february, we have this rfc below:

Network Working Group D.
Request for Comments: 1912 The Pennsylvania State
Obsoletes: 1537 February 1996
Category:

Common DNS Operational and Configuration

Status of this

This memo provides information for the Internet community. This
does not specify an Internet standard of any kind. Distribution
this memo is unlimited

This memo describes errors often found in both the operation
Domain Name System (DNS) servers, and in the data that these
servers contain. This memo tries to summarize current
requirements as well as common practice in the operation
configuration of the DNS. This memo also tries to summarize
expand upon issues raised in [RFC 1537].

1.

Running a nameserver is not a trivial task. There are many
that can go wrong, and many decisions have to be made about what
to put in the DNS and how to set up servers. This memo attempts
address many of the common mistakes and pitfalls that are made in
data as well as in the operation of nameservers. Discussions
also made regarding some other relevant issues such as server
resolver bugs, and a few political issues with respect to
operation of DNS on the Internet

2. DNS

This section discusses problems people typically have with the
data in their nameserver, as found in the zone data files that
nameserver loads into memory

2.1 Inconsistent, Missing, or Bad

Every Internet-reachable host should have a name. The
of this are becoming more and more obvious. Many services
on the Internet will not talk to you if you aren't
registered in the DNS

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Make sure your PTR and A records match. For every IP address,
should be a matching PTR record in the in-addr.arpa domain. If
host is multi-homed, (more than one IP address) make sure that all
addresses have a corresponding PTR record (not just the first one).
Failure to have matching PTR and A records can cause loss of
services similar to not being registered in the DNS at all. Also
PTR records must point back to a valid A record, not a alias
by a CNAME. It is highly recommended that you use some
which automates this checking, or generate your DNS data from
database which automatically creates consistent data

DNS domain names consist of "labels" separated by single dots.
DNS is very liberal in its rules for the allowable characters in
domain name. However, if a domain name is used to name a host,
should follow rules restricting host names. Further if a name
used for mail, it must follow the naming rules for names in
addresses

Allowable characters in a label for a host name are only
letters, digits, and the `-' character. Labels may not be
numbers, but may have a leading digit (e.g., 3com.com). Labels
end and begin only with a letter or digit. See [RFC 1035] and [
1123]. (Labels were initially restricted in [RFC 1035] to start
a letter, and some older hosts still reportedly have problems
the relaxation in [RFC 1123].) Note there are some
hostnames which violate this rule (411.org, 1776.com). The
of underscores in a label is allowed in [RFC 1033], except [RFC 1033]
is informational only and was not defining a standard. There is
least one popular TCP/IP implementation which currently refuses
talk to hosts named with underscores in them. It must be noted
the language in [1035] is such that these rules are voluntary --
are there for those who wish to minimize problems. Note that
rules for Internet host names also apply to hosts and addresses
in SMTP (See RFC 821).

If a domain name is to be used for mail (not involving SMTP), it
follow the rules for mail in [RFC 822], which is actually
liberal than the above rules. Labels for mail can be any
character except "specials", control characters, and
characters. "Specials" are specific symbols used in the parsing
addresses. They are the characters "()<>@,;:\".[]". (The "!"
character wasn't in [RFC 822], however it also shouldn't be used
to the conflict with UUCP mail as defined in RFC 976) However,
today almost all names which are used for mail on the Internet
also names used for hostnames, one rarely sees addresses using
relaxed standard, but mail software should be made liberal and
enough to accept them

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You should also be careful to not have addresses which are
alternate syntaxes to the inet_ntoa() library call. For example 0
is a valid name, but if you were to type "telnet 0xe", it would
to connect to IP address 0.0.0.14. It is also rumored that
exists some broken inet_ntoa() routines that treat an address
x400 as an IP address

Certain operating systems have limitations on the length of their
hostname. While not strictly of issue to the DNS, you should
aware of your operating system's length limits before choosing
name of a host

Remember that many resource records (abbreviated RR) take on
than one argument. HINFO requires two arguments, as does RP. If
don't supply enough arguments, servers sometime return garbage
the missing fields. If you need to include whitespace within
data, you must put the string in quotes

2.2 SOA

In the SOA record of every zone, remember to fill in the e-
address that will get to the person who maintains the DNS at
site (commonly referred to as "hostmaster"). The `@' in the e-
must be replaced by a `.' first. Do not try to put an `@' sign
this address. If the local part of the address already contains
`.' (e.g., John.Smith@widget.xx), then you need to quote the `.'
preceding it with `\' character. (e.g., to
John\.Smith.widget.xx) Alternately (and preferred), you can just
the generic name `hostmaster', and use a mail alias to redirect it
the appropriate persons. There exists software which uses this
to automatically generate the e-mail address for the zone contact
This software will break if this field is improperly formatted.
is imperative that this address get to one or more real persons
because it is often used for everything from reporting bad DNS
to reporting security incidents

Even though some BIND versions allow you to use a decimal in a
number, don't. A decimal serial number is converted to an
32-bit integer internally anyway. The formula for a n.m
number is n*10^(3+int(0.9+log10(m))) + m which translates
something rather unexpected. For example it's routinely
with a decimal serial number (perhaps automatically generated
SCCS) to be incremented such that it is numerically larger, but
the above conversion yield a serial number which is LOWER
before. Decimal serial numbers have been officially deprecated
recent BIND versions. The recommended syntax is
(YYYY=year, MM=month, DD=day, nn=revision number. This won'
overflow until the year 4294.

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Choose logical values for the timer values in the SOA record (
values below must be expressed as seconds in the zone data):

Refresh: How often a secondary will poll the primary server to
if the serial number for the zone has increased (so it
to request a new copy of the data for the zone). Set this
how long your secondaries can comfortably contain out-of-
data. You can keep it short (20 mins to 2 hours) if
aren't worried about a small increase in bandwidth used,
longer (2-12 hours) if your Internet connection is slow or
started on demand. Recent BIND versions (4.9.3) have
code to automatically notify secondaries that data
changed, allowing you to set this TTL to a long value (
day, or more).

Retry: If a secondary was unable to contact the primary at
last refresh, wait the retry value before trying again.
value isn't as important as others, unless the secondary is
a distant network from the primary or the primary is
prone to outages. It's typically some fraction of the
interval

Expire: How long a secondary will still treat its copy of the
data as valid if it can't contact the primary. This
should be greater than how long a major outage would
last, and must be greater than the minimum and
intervals, to avoid having a secondary expire the data
it gets a chance to get a new copy. After a zone is expired
secondary will still continue to try to contact the primary
but it will no longer provide nameservice for the zone. 2-4
weeks are suggested values

Minimum: The default TTL (time-to-live) for resource records --
how long data will remain in other nameservers' cache. ([
1035] defines this to be the minimum value, but servers
to always implement this as the default value) This is by
the most important timer. Set this as large as is
given how often you update your nameserver. If you plan
make major changes, it's a good idea to turn this value
temporarily beforehand. Then wait the previous minimum value
make your changes, verify their correctness, and turn
value back up. 1-5 days are typical values. Remember
value can be overridden on individual resource records

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As you can see, the typical values above for the timers vary widely
Popular documentation like [RFC 1033] recommended a day for
minimum TTL, which is now considered too low except for zones
data that vary regularly. Once a DNS stabilizes, values on the
of 3 or more days are recommended. It is also recommended that
individually override the TTL on certain RRs which are
referenced and don't often change to have very large values (1-2
weeks). Good examples of this are the MX, A, and PTR records of
mail host(s), the NS records of your zone, and the A records of
nameservers

2.3 Glue A

Glue records are A records that are associated with NS records
provide "bootstrapping" information to the nameserver. For example

podunk.xx. in ns ns1.podunk.xx
in ns ns2.podunk.xx
ns1.podunk.xx. in a 1.2.3.4
ns2.podunk.xx. in a 1.2.3.5

Here, the A records are referred to as "Glue records".

Glue records are required only in forward zone files for
that are located in the subdomain of the current zone that is
delegated. You shouldn't have any A records in an in-addr.arpa
file (unless you're using RFC 1101-style encoding of subnet masks).

If your nameserver is multi-homed (has more than one IP address),
must list all of its addresses in the glue to avoid
inconsistency due to differing TTL values, causing some lookups
not find all addresses for your nameserver

Some people get in the bad habit of putting in a glue record
they add an NS record "just to make sure". Having duplicate
records in your zone files just makes it harder when a
moves to a new IP address, or is removed. You'll spend hours
to figure out why random people still see the old IP address for
host, because someone forgot to change or remove a glue record
some other file. Newer BIND versions will ignore these extra
records in local zone files

Older BIND versions (4.8.3 and previous) have a problem where
inserts these extra glue records in the zone transfer data
secondaries. If one of these glues is wrong, the error can
propagated to other nameservers. If two nameservers are
for other zones of each other, it's possible for one to
pass old glue records back to the other. The only way to get rid

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the old data is to kill both of them, remove the saved backup files
and restart them. Combined with that those same versions also
to become infected more easily with bogus data found in other non
secondary nameservers (like the root zone data).

2.4 CNAME

A CNAME record is not allowed to coexist with any other data.
other words, if suzy.podunk.xx is an alias for sue.podunk.xx,
can't also have an MX record for suzy.podunk.edu, or an A record,
even a TXT record. Especially do not try to combine CNAMEs and
records like this!:

podunk.xx. IN NS ns
IN NS ns
IN CNAME
mary IN A 1.2.3.4

This is often attempted by inexperienced administrators as an
way to allow your domain name to also be a host. However,
servers like BIND will see the CNAME and refuse to add any
resources for that name. Since no other records are allowed
coexist with a CNAME, the NS entries are ignored. Therefore all
hosts in the podunk.xx domain are ignored as well

If you want to have your domain also be a host, do the following

podunk.xx. IN NS ns
IN NS ns
IN A 1.2.3.4
mary IN A 1.2.3.4

Don't go overboard with CNAMEs. Use them when renaming hosts,
plan to get rid of them (and inform your users). However CNAMEs
useful (and encouraged) for generalized names for servers -- `ftp
for your ftp server, `www' for your Web server, `gopher' for
Gopher server, `news' for your Usenet news server, etc

Don't forget to delete the CNAMEs associated with a host if
delete the host it is an alias for. Such "stale CNAMEs" are a
of resources

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Don't use CNAMEs in combination with RRs which point to other
like MX, CNAME, PTR and NS. (PTR is an exception if you want
implement classless in-addr delegation.) For example, this
strongly discouraged

podunk.xx. IN MX
mailhost IN CNAME
mary IN A 1.2.3.4

[RFC 1034] in section 3.6.2 says this should not be done, and [
974] explicitly states that MX records shall not point to an
defined by a CNAME. This results in unnecessary indirection
accessing the data, and DNS resolvers and servers need to work
to get the answer. If you really want to do this, you can
the same thing by using a preprocessor such as m4 on your host files

Also, having chained records such as CNAMEs pointing to CNAMEs
make administration issues easier, but is known to tickle bugs
some resolvers that fail to check loops correctly. As a result
hosts may not be able to resolve such names

Having NS records pointing to a CNAME is bad and may conflict
with current BIND servers. In fact, current BIND
will ignore such records, possibly leading to a lame delegation
There is a certain amount of security checking done in BIND
prevent spoofing DNS NS records. Also, older BIND servers
will get caught in an infinite query loop trying to figure out
address for the aliased nameserver, causing a continuous stream
DNS requests to be sent

2.5 MX

It is a good idea to give every host an MX record, even if it
to itself! Some mailers will cache MX records, but will always
to check for an MX before sending mail. If a site does not have
MX, then every piece of mail may result in one more resolver query
since the answer to the MX query often also contains the IP
of the MX hosts. Internet SMTP mailers are required by [RFC 1123]
support the MX mechanism

Put MX records even on hosts that aren't intended to send or
e-mail. If there is a security problem involving one of these hosts
some people will mistakenly send mail to postmaster or root at
site without checking first to see if it is a "real" host or just
terminal or personal computer that's not set up to accept e-mail.
you give it an MX record, then the e-mail can be redirected to a
person. Otherwise mail can just sit in a queue for hours or

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until the mailer gives up trying to send it

Don't forget that whenever you add an MX record, you need to
the target mailer if it is to treat the first host as "local". (
"Cw" flag in sendmail, for example

If you add an MX record which points to an external host (e.g.,
the purposes of backup mail routing) be sure to ask permission
that site first. Otherwise that site could get rather upset and
action (like throw your mail away, or appeal to higher
like your parent DNS administrator or network provider.)

2.6 Other Resource

2.6.1

WKS records are deprecated in [RFC 1123]. They serve no known
function, except internally among LISP machines. Don't use them

2.6.2

On the issue HINFO records, some will argue that these is a
problem (by broadcasting what vendor hardware and operating
you so people can run systematic attacks on known vendor
holes). If you do use them, you should keep up to date with
vendor security problems. However, they serve a useful purpose
Don't forget that HINFO requires two arguments, the hardware type
and the operating system

HINFO is sometimes abused to provide other information. The
is meant to provide specific information about the machine itself
If you need to express other information about the host in the DNS
use TXT

2.6.3

TXT records have no specific definition. You can put most
in them. Some use it for a generic description of the host, some
specific information like its location, primary user, or maybe even
phone number

2.6.4

RP records are relatively new. They are used to specify an e-
address (see first paragraph of section 2.2) of the "
Person" of the host, and the name of a TXT record where you can
more information. See [RFC 1183].

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2.7 Wildcard

Wildcard MXs are useful mostly for non IP-connected sites. A
mistake is thinking that a wildcard MX for a zone will apply to
hosts in the zone. A wildcard MX will apply only to names in
zone which aren't listed in the DNS at all. e.g.,

podunk.xx. IN NS ns
IN NS ns
mary IN A 1.2.3.4
*.podunk.xx. IN MX 5

Mail for mary.podunk.xx will be sent to itself for delivery.
mail for jane.podunk.xx or any hosts you don't see above will be
to the MX. For most Internet sites, wildcard MX records are
useful. You need to put explicit MX records on every host

Wildcard MXs can be bad, because they make some operations
when they should fail instead. Consider the case where someone
the domain "widget.com" tries to send mail to "joe@larry". If
host "larry" doesn't actually exist, the mail should in fact
immediately. But because of domain searching the address
resolved to "larry.widget.com", and because of the wildcard MX
is a valid address according to DNS. Or perhaps someone simply
a typo in the hostname portion of the address. The mail message
gets routed to the mail host, which then rejects the mail
strange error messages like "I refuse to talk to myself" or "
configuration error".

Wildcard MX records are good for when you have a large number
hosts which are not directly Internet-connected (for example,
a firewall) and for administrative or political reasons it is
difficult to have individual MX records for every host, or to
all e-mail addresses to be "hidden" behind one or more domain names
In that case, you must divide your DNS into two parts, an
DNS, and an external DNS. The external DNS will have only a
hosts and explicit MX records, and one or more wildcard MXs for
internal domain. Internally the DNS will be complete, with
explicit MX records and no wildcards

Wildcard As and CNAMEs are possible too, and are really confusing
users, and a potential nightmare if used without thinking first.
could result (due again to domain searching) in any telnet/
attempts from within the domain to unknown hosts to be directed
one address. One such wildcard CNAME (in *.edu.com)
Internet-wide loss of services and potential security nightmares
to unexpected interactions with domain searching. It resulted
swift fixes, and even an RFC ([RFC 1535]) documenting the problem

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2.8 Authority and Delegation Errors (NS records

You are required to have at least two nameservers for every domain
though more is preferred. Have secondaries outside your network.
the secondary isn't under your control, periodically check up on
and make sure they're getting current zone data from you. Queries
their nameserver about your hosts should always result in
"authoritative" response. If not, this is called a "
delegation". A lame delegations exists when a nameserver
delegated responsibility for providing nameservice for a zone (via
records) but is not performing nameservice for that zone (
because it is not set up as a primary or secondary for the zone).

The "classic" lame delegation can be illustrated in this example

podunk.xx. IN NS ns1.podunk.xx
IN NS ns0.widget.com

"podunk.xx" is a new domain which has recently been created,
"ns1.podunk.xx" has been set up to perform nameservice for the zone
They haven't quite finished everything yet and haven't made sure
the hostmaster at "ns0.widget.com" has set up to be a
secondary, and thus has no information about the podunk.xx domain
even though the DNS says it is supposed to. Various things
happen depending on which nameserver is used. At best, extra
traffic will result from a lame delegation. At worst, you can
unresolved hosts and bounced e-mail

Also, sometimes a nameserver is moved to another host or removed
the list of secondaries. Unfortunately due to caching of NS records
many sites will still think that a host is a secondary after
host has stopped providing nameservice. In order to prevent
delegations while the cache is being aged, continue to
nameservice on the old nameserver for the length of the maximum
the minimum plus refresh times for the zone and the parent zone
(See section 2.2)

Whenever a primary or secondary is removed or changed, it takes
fair amount of human coordination among the parties involved. (
site itself, it's parent, and the site hosting the secondary) When
primary moves, make sure all secondaries have their named.boot
updated and their servers reloaded. When a secondary moves,
sure the address records at both the primary and parent level
changed

It's also been reported that some distant sites like to pick
nameservers like "ns.uu.net" and just add it to their list of
records in hopes that they will magically perform

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nameservice for them. This is an even worse form of lame delegation
since this adds traffic to an already busy nameserver.
contact the hostmasters of sites which have lame delegations
Various tools can be used to detect or actively find
delegations. See the list of contributed software in the
distribution

Make sure your parent domain has the same NS records for your zone
you do. (Don't forget your in-addr.arpa zones too!). Do not
too many (7 is the recommended maximum), as this just makes
harder to manage and is only really necessary for very popular top
level or root zones. You also run the risk of overflowing the 512-
byte limit of a UDP packet in the response to an NS query. If
happens, resolvers will "fall back" to using TCP requests,
in increased load on your nameserver

It's important when picking geographic locations for
nameservers to minimize latency as well as increase reliability
Keep in mind network topologies. For example if your site is on
other end of a slow local or international link, consider a
on the other side of the link to decrease average latency.
your Internet service provider or parent domain contact for
information about secondaries which may be available to you

3. BIND

This section discusses common problems people have in the
operation of the nameserver (specifically, BIND). Not only must
data be correct as explained above, but the nameserver must
operated correctly for the data to be made available

3.1 Serial

Each zone has a serial number associated with it. Its use is
keeping track of who has the most current data. If and only if
primary's serial number of the zone is greater will the secondary
the primary for a copy of the new zone data (see special case below).

Don't forget to change the serial number when you change data!
you don't, your secondaries will not transfer the new
information. Automating the incrementing of the serial number
software is also a good idea

If you make a mistake and increment the serial number too high,
you want to reset the serial number to a lower value, use
following procedure

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Take the `incorrect' serial number and add 2147483647 to it.
the number exceeds 4294967296, subtract 4294967296. Load
resulting number. Then wait 2 refresh periods to allow the
to propagate to all servers

Repeat above until the resulting serial number is less than
target serial number

Up the serial number to the target serial number

This procedure won't work if one of your secondaries is running
old version of BIND (4.8.3 or earlier). In this case you'll have
contact the hostmaster for that secondary and have them kill
secondary servers, remove the saved backup file, and restart
server. Be careful when editing the serial number -- DNS
don't like to kill and restart nameservers because you lose all
cached data

3.2 Zone file style

Here are some useful tips in structuring your zone files.
these will help you spot mistakes, and avoid making more

Be consistent with the style of entries in your DNS files. If
$ORIGIN is podunk.xx., try not to write entries like

mary IN A 1.2.3.1
sue.podunk.xx. IN A 1.2.3.2

or

bobbi IN A 1.2.3.2
IN MX mary.podunk.xx

Either use all FQDNs (Fully Qualified Domain Names) everywhere
used unqualified names everywhere. Or have FQDNs all on the right
hand side but unqualified names on the left. Above all,
consistent

Use tabs between fields, and try to keep columns lined up. It
it easier to spot missing fields (note some fields such as "IN"
inherited from the previous record and may be left out in
circumstances.)

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Remember you don't need to repeat the name of the host when you
defining multiple records for one host. Be sure also to keep
records associated with a host together in the file. It will
things more straightforward when it comes time to remove or rename
host

Always remember your $ORIGIN. If you don't put a `.' at the end
an FQDN, it's not recognized as an FQDN. If it is not an FQDN,
the nameserver will append $ORIGIN to the name. Double check,
check, those trailing dots, especially in in-addr.arpa zone files
where they are needed the most

Be careful with the syntax of the SOA and WKS records (the
which use parentheses). BIND is not very flexible in how it
these records. See the documentation for BIND

3.3 Verifying

Verify the data you just entered or changed by querying the
with dig (or your favorite DNS tool, many are included in the
distribution) after a change. A few seconds spent double
can save hours of trouble, lost mail, and general headaches. Also
sure to check syslog output when you reload the nameserver. If
have grievous errors in your DNS data or boot file, named will
it via syslog

It is also highly recommended that you automate this checking,
with software which runs sanity checks on the data files before
are loaded into the nameserver, or with software which checks
data already loaded in the nameserver. Some contributed software
do this is included in the BIND distribution

4. Miscellaneous

4.1 Boot file

Certain zones should always be present in nameserver configurations

primary localhost
primary 0.0.127.in-addr.arpa 127.0
primary 255.in-addr.arpa 255
primary 0.in-addr.arpa 0

These are set up to either provide nameservice for "special
addresses, or to help eliminate accidental queries for broadcast
local address to be sent off to the root nameservers. All of
files will contain NS and SOA records just like the other zone
you maintain, the exception being that you can probably make the

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timers very long, since this data will never change

The "localhost" address is a "special" address which always refers
the local host. It should contain the following line

localhost. IN A 127.0.0.1

The "127.0" file should contain the line

1 PTR localhost

There has been some extensive discussion about whether or not
append the local domain to it. The conclusion is that "localhost."
would be the best solution. The reasons given include

"localhost" by itself is used and expected to work in
systems

Translating 127.0.0.1 into "localhost.dom.ain" can cause
software to connect back to the loopback interface when it didn'
want to because "localhost" is not equal to "localhost.dom.ain".

The "255" and "0" files should not contain any additional data
the NS and SOA records

Note that future BIND versions may include all or some of this
automatically without additional configuration

4.2 Other Resolver and Server

Very old versions of the DNS resolver have a bug that cause
for names that look like IP addresses to go out, because the
supplied an IP address and the software didn't realize that it didn'
need to be resolved. This has been fixed but occasionally it
pops up. It's important because this bug means that these
will be sent directly to the root nameservers, adding to an
heavy DNS load

While running a secondary nameserver off another secondary
is possible, it is not recommended unless necessary due to
topologies. There are known cases where it has led to problems
bogus TTL values. While this may be caused by older or flawed
implementations, you should not chain secondaries off of one
since this builds up additional reliability dependencies as well
adds additional delays in updates of new zone data

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4.3 Server

DNS operates primarily via UDP (User Datagram Protocol) messages
Some UNIX operating systems, in an effort to save CPU cycles,
with UDP checksums turned off. The relative merits of this have
been debated. However, with the increase in CPU speeds,
performance considerations become less and less important. It
strongly encouraged that you turn on UDP checksumming to
corrupted data not only with DNS but with other services that use
(like NFS). Check with your operating system documentation to
that UDP checksumming is enabled

[RFC 974] Partridge, C., "Mail routing and the domain system",
14, RFC 974, CSNET CIC BBN Laboratories Inc, January 1986.

[RFC 1033] Lottor, M, "Domain Administrators Operations Guide",
1033, USC/Information Sciences Institute, November 1987.

[RFC 1034] Mockapetris, P., "Domain Names - Concepts and Facilities",
STD 13, RFC 1034, USC/Information Sciences Institute
November 1987.

[RFC 1035] Mockapetris, P., "Domain Names - Implementation
Specification", STD 13, RFC 1035, USC/Information
Institute, November 1987.

[RFC 1123] Braden, R., "Requirements for Internet Hosts --
Application and Support", STD 3, RFC 1123, IETF,
1989.

[RFC 1178] Libes, D., "Choosing a Name for Your Computer", FYI 5,
1178, Integrated Systems Group/NIST, August 1990.

[RFC 1183] Ullman, R., Mockapetris, P., Mamakos, L, and C. Everhart
"New DNS RR Definitions", RFC 1183, October 1990.

[RFC 1535] Gavron, E., "A Security Problem and Proposed
With Widely Deployed DNS Software", RFC 1535,
Research Inc., October 1993.

[RFC 1536] Kumar, A., Postel, J., Neuman, C., Danzig, P., and S
Miller, "Common DNS Implementation Errors and
Fixes", RFC 1536, USC/Information Sciences Institute, USC
October 1993.

Barr Informational [Page 15]

RFC 1912 Common DNS Errors February 1996

[RFC 1537] Beertema, P., "Common DNS Data File Configuration Errors",
RFC 1537, CWI, October 1993.

[RFC 1713] A. Romao, "Tools for DNS debugging", RFC 1713, FCCN
November 1994.

[BOG] Vixie, P, et. al., "Name Server Operations Guide for BIND",
Vixie Enterprises, July 1994.

5. Security

Security issues are not discussed in this memo

6. Author's

David
The Pennsylvania State
Department of
334 Whitmore
University Park, PA 16802

Voice: +1 814 863 7374
Fax: +1 814 863-8311
EMail: barr@math.psu.

Barr Informational [Page 16]

if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.

RFC documents can be found at I.E.T.F.

Relevance System Copyright © 2002 Spectrum WorldResearch
other technical nosh by ServerMasters Corporation
collaboration of BobX