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Solaris uses an open source DNS implementation called BIND (Berkeley Internet Name Domain) as its DNS daemon. BIND (Berkeley Internet Name Domain) is the oldest implementation of the DNS protocol that can be traced to original BSD systems.
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Contrary to popular urban myth Paul Vixie did nit write the original BIND. As Kevin Oberman recollected:
The first BIND version (4.3?) was written by the CSRG at UC Berkeley by Kevin Dunlap who was on loan to CSRG by Digital (who also employed Paul at that time). When Paul took over support of BIND at about 4.4, it was a horrid mess and rapidly moving toward death. After some fixes and clean-up of the code, the first real BIND from Paul was 4.8. ISC (including Paul) wrote BIND 8. BIND 9 was contracted out to Nominum and one of the stipulations was that the existing code base could not be used at all and another was that the team that wrote BIND 8 should not work on BIND 9. For that (and other) reason, Paul did not write any of BIND 9
In his comment to the letter Paul Vixie clarified some facts:
> Well, Paul Vixie wrote bind
nope. kevin dunlap and other folks at U C Berkeley wrote BIND originally. all i did was fork the code base at 4.8.3, produce King James BIND, then BIND 4.9 through BIND 8.1, and along the way co-founded ISC with rick adams. also along the way i won the "most cert advisories by a single author" award (which noone has been willing to try to take away from me) and stopped coding. i'm pleased to announce that BIND9 has no code from BIND8 or BIND4 in it, and also no code from me in it.
--- [email protected] ("Kevin Oberman") writes:
> Paul Vixie did NOT write the original BIND. The first BIND version
> (4.3?) was written by the CSRG at UC Berkeley by Kevin Dunlap who was on
> loan to CSRG by Digital (who also employed Paul at that time).
no, i was employed by Digital later, long after kevin dunlap had moved on.
> When Paul took over support of BIND at about 4.4,
4.8.3.
> it was a horrid mess and rapidly moving toward death.
and there were other code forks besides mine. what distinguished my work
was that i merged in every change i could understand from every other fork.
(that's why i called it King James BIND, for you literary history buffs.)
> After some fixes and clean-up of the
> code, the first real BIND from Paul was 4.8.
4.9.
> ISC (including Paul) wrote BIND 8.
john gilmore and bob halley had a LOT to do with the creation of BIND8 btw.
(john also taught me to use CVS rather than RCS, to my great betterment,
and he wrote some early DNSSEC code, and negotiated a licensing deal between
RSADSI and ISC... he's an unsung hero in the BIND revolution.)
> BIND 9 was contracted out to Nominum
internet engines. Which later became nominum.
> and one of the stipulations was that the existing code base could not be
> used at all and another was that the team that wrote BIND 8 should not
> work on BIND 9.
actually, bob halley worked on both BIND8 and BIND9.
> For that (and other) reason, Paul did not write any of BIND 9.
yea, verily.
--- [email protected] (David Conrad) writes:
> However, I don't speak authoritatively (pun intended) on BIND.
and yet, for the record, i agree with everything drc said in his note today.
--
Paul Vixie
The source code is licensed under BSD license and includes implementation of:
When you are working with BIND it's evident how old it is and how people who developed various packages for it were unable to understand the "spirit of Unix" and come with kluges that contradict Unix philosophy, but for some reason stay with us for decades. Actually first implementations of DNS servers were for the TOPS-20 operating system in 1983.
Still BIND is a pretty vivid demonstration of inability of designers of Unix packages to grasp the spirit of Unix :-) And while the general DNS architecture is sound the BIND implementation was (until version 9 let's hope) a very questionable security-wise. Administration-wise it continues to be challenging to say the least. IMHO administration was done unnecessary complex by configuration files that are far from being human-friendly and have subtle interdependencies that for some unexplainable reason need to be resolved manually (many scripts exist for this purpose and at least couple of them should probably be used by every non-masochistic DNS admin).
The structure of DNS configuration files can serve as a good example of how old data-related mini-languages survive in software packages. And they can be quite horrible mess even if the code written by above average programmers. Even in Bind 9 the configuration files remain very cumbersome and their maintenance time consuming and error prone.
Currently the second (or third) generation of Unix administrators needs to suffer from all those unnecessary complexity. In a sense BIND is the greatest failure of open source programming model. Despite its critical role in Internet infrastructure BIND 4 and 8 were probably one of the most "security-challenged" open source applications widely deployed. At least until version 9 was released. For decades it was pretty unusual not have a bind exploit each second quarter. Not that all of those exploit were really dangerous, but still the feeling was that one needs to upgrade and countless hours were spend on countless upgrade of bind by each organization with its own nameserver.
BIND's complexity provided a windows opportunity for book publishers and I believe O'Reilly got a neat revenue from selling four editions of BIND book.
Alternative implementations of DNS servers exist including several open source packages but none get the same level of prominence as original BIND. Of alternative free packages only D. J. Bernstein's djbdns got some traction due to it significantly higher level of security: it is sometimes called "Continuous DNS service without continual software upgrades" :-)
As of Jan 2006 current versions from Internet Systems Consortium, Inc. are
You should recompile those versions using Studio 11 or download the latest precompiled version from Solaris freeware site. It does not make sense to preserve the version that comes with Solaris 9 or 10.
In Solaris the daemon in.named is by default placed in /usr/sbin/ . It is stared during system boot if the /etc/named.conf file exists. When configuring nameserver, you need to supply the following information in your /etc/named.conf and files that it refers to (so called DNS resource records) :
Names and addresses of root servers.
The information needed to resolve all domains for which the server is authoritative. Those records, called A records provide name to address translation.
The information needed to resolve all inverse domains for which the server is authoritative. Those records called IN records provide address to name translation (construction of IN records can be automated as all information necessary is contains in A-record
Names and addresses of servers for all domains one level below the domain being served by this server. This is sometimes referred to as parenting or delegating.
All of this information is supplied in configuration files referred to by the BIND configuration file /etc/named. conf and loaded into the in . named cache.
There are two major versions of BIND daemon: version 8 and version 9. Solaris 9 uses BIND 8.x.x implementation. Solaris 10 uses 9.x.x implementation.
/etc/named.conf configuration file determines if the server is a primary, secondary, or cache-only name server. It also specifies the zones over which the server has authority and which data files it should read to get its initial data.
The/etc/named.conf file consists of statements possibly separated by blank lines. Each statement should end with a semicolon. Some statements can contain a block of statements in curvy brackets. Again, each statement in the block is terminated with a semicolon.
There are several major types of named.conf statements. Four are used in the example below:
options Controls global server configuration options and sets default values for other statements.
zone Defines a zone. Selectively applies options on a per-zone basis, rather than to all zones.
file Defines an include file that contains so called called DNS resource records. Is used to break up the configuration into more easily managed chunks.
type Sets designated type associated with a server.
Here is an example of the BIND configuration file /etc/named. conf and its relationship to name server data files.
options {
DIRECTORY "/var/named";
};
zone "." in {
type hint;
file "named.root";
};
zone "softpanorama.org" in {
type master;
file "softpanorama.org.zone";
};
zone "10.10.10.in-addr.arpa" in {
type master;
file "softpanorama.org.rzone";
};
zone "127.in-addr.arpa" in {
type master;
file "loopback-domain-info";
};
Other statements include:
Dr. Nikolai Bezroukov
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The configuration of each DNS server type is slightly different. In this objective the following is discussed:
- Configure a Caching-Only DNS Server
- Configure a Master Server for Your Domain
- Configure One or More Slave Servers
June 2000 | Sun
You never know when the set up for a trade show, demo, lab, or other project might come to a loggerhead because someone needs a robust internet domain name server (DNS). The function of the DNS is to act as the server that client applications contact to resolve an IP address from the host name. The IP address is then used by network routers to send data packets to the remote server.
In reverse mode, the DNS can also resolve host names when given an IP address. Many UNIX applications use this method to perform security checks, Address Resolution Protocol (ARP), or Reverse Address Resolution Protocol (RARP) to verify that the host name data and IP address do indeed match. For example, if you try to Telnet or FTP to a Solaris host from a renegade laptop using a valid but unresolvable IP address on the LAN, you may notice that it can take up to 60 seconds to receive the login prompt. You can fix this delay by simply adding an entry for host name and IP address into the maps on the primary network DNS.
Setting up a DNS from scratch can be complicated. Although you can read the man pages and generate valid map files from scratch, it is not very efficient. A better way is to follow an example template provided in the next section.
Unpacking Instructions
Download this template to a work directory, such as
/var
. To unpack the file, at the command line type:zcat name.tar.Z | tar xvf -Fast Installation Overview
For quick installation, do the following:
- Determine what type of DNS you want and what support information you need from your network provider, such as global caching DNS.
- Edit the
named.*
files you need. For releases prior to Solaris 7, usenamed.boot
,named.local
,named.cache
,named.mydomain
, andnamed.mydomain.rev
. For Solaris 7 and Solaris 8, the map files are the same, but edit thenamed.conf
instead ofnamed.boot
.- Edit the
/etc/resolv.conf
file. It should look like the following:domain mydomain.com nameserver 127.0.0.1 ;if DNS server runs on this host nameserver 129.200.9.1 ;if this is a remote client
- Create a symbolic link in
/etc/
to either thenamed.boot
ornamed.conf
file and start the DNS (/usr/sbin/in.named
).- You can verify the DNS is working properly by running some queries to test forward and reverse resolution.
Detailed Installation
- Determine what kind of DNS you need.
If you are at a trade show and without Internet access, you need to be a primary.
If you are at a trade show and have Internet access, find the ISP and ask whether they have (a) a world resolvable caching DNS and (b) a primary for the show floor.
- If they have (a) but not (b), you will need to be a primary for this subnet. Any reputable ISP will have at least (a).
- If they have both (a) and (b), but are unreliable for (b), you should be a secondary.
- If (b) does not have a complete map or maps, you may need to create your own primary for that subnet.
If you are just starting a new subnet (e.g. you are at a startup company and the person who knows anything about network administration is the IT person), then you probably want to be your own primary for the subnet. You should talk it over with your ISP. If your ISP is responsive and reliable, and doesn't mind that you constantly re-assign IP addresses and hosts, you should use them as your primary. Otherwise, if you are planning to do some very complicated DHCP, IP address sharing, NAT, or network customization, you probably should be your own primary. In other words, if you want your network to be resolvable and routable outside of your network, you may want to arrange with your ISP to give you primary domain DNS control for your subnet and have the ISP act as a "secondary" to your subnet domain. This configuration is common at many large universities. For example, each department or college group manages its own subnet within a large Class A or B network. The institution's top level DNS is actually a secondary for the various smaller subnet primaries.
If you need to resolve Internet host names outside of the corporate network, but have an inadequate primary DNS on your network, you should become a secondary DNS for your local subnet. You can also add a
forwarders
entry to the corporate top-level gateway DNS so that you can resolve IP addresses outside of the corporate network. Other people can then configure their hosts to use your DNS as their default to use these features.- If you are running Solaris 7 or Solaris 8, examine the
named.conf
file. Each file is self explanatory and you can copy the/etc/hosts
file and add Authoritative records (A) and pointer records (PTR) to your maps.Note: For Solaris 7 users who are familiar with BIND8 (old) format
named.boot
files and want to convert them to the new BIND9 formatnamed.conf
files, you can run the/usr/sbin/named-bootconf -i infile -o outfile
utility.Edit all the files you need, usually:
- Mandatory files
named.boot
ornamed.conf
(depending on OS version)
named.cache
named.local
- Optional files (for primary DNS)
named.mydomain
named.mydomain.rev
[other reverse or forward maps]You may have multiple forward and reverse maps because this DNS may be supporting multiple domain names and subnets.
- Edit the
/etc/resolv.conf
file. It should look like the following:domain mydomain.com nameserver 127.0.0.1 ;if DNS server runs on this host nameserver 129.200.9.1 ;if this is a remote clientYou can have multiple DNS entries in the
resolv.conf
file. Each entry is searched in top-to-bottom order until the server responds, or times out. Therefore, you should put the server that is the most robust and responds the fastest at the top of the list. When a DNS is successfully queried, it is general practice for the client to use only that server for querying, even if the DNS responds that there are no entries. If the DNS you configured to use on the client is not resolving all of the hosts you know exist, you should contact the administrator for that DNS or simply change to a server that can resolve all the names. If a DNS server is down, you may experience a long wait before the client application fails and switches to use the next DNS. This can vary from 15 to 60 seconds per DNS entry in theresolv.conf
file. If you are experiencing DNS resolution delays repeatedly and have access to another server, you should change theresolv.conf
file to use another DNS.
- Create a symbolic link in
/etc/
to either thenamed.boot
ornamed.conf
file. For example, if you unpacked the file in/var/named
on a Solaris 2.6 system, type at the command line:ln -s /var/named/named.boot /etc/named.bootStart the DNS server by typing:
/usr/sbin/in.named- Test the DNS by running some queries to test forward and reverse resolution. You can use the following forward test:
/usr/sbin/nslookup myhostA sample response looks like:
Server: localhost Address: 127.0.0.1 Name: myhost.mydomain.com Address: 129.200.9.1You should repeat your test using an IP address instead:
/usr/sbin/nslookup 129.200.9.2A sample response looks like:
Server: localhost Address: 127.0.0.1 Name: myhost2.mydomain.com Address: 129.200.9.2If the DNS is set up to resolve Internet addresses, you can test this by typing:
/usr/sbin/nslookup nuc.berkeley.edu
A sample response looks like:
Server: localhost Address: 127.0.0.1 Non-authoritative answer: Name: nuc.berkeley.edu Address: 128.32.142.96Disclaimer
This template is supplied "AS IS" without support or warranties.
BIND 9 is new in the Solaris Express 8/04 release. In the Solaris 10 3/05 release, the BIND version was upgraded to BIND version 9.2.4.
BIND is an open source implementation of DNS. BIND is developed by the Internet Systems Consortium (ISC). BIND allows DNS clients and applications to query DNS servers for the IPv4 and IPv6 networks. BIND includes two main components: a stub resolver API, resolver(3resolv), and the DNS name server with various DNS tools.
BIND enables DNS clients to connect to IPv6 DNS servers by using IPv6 transport. BIND provides a complete DNS client-server solution for IPv6 networks.
BIND 9.2.4 is a redesign of the DNS name server and tools by the Internet Systems Consortium (ISC). The BIND version 9.2.4 nameserver and tools are available in the Solaris 10 OS.
BIND 8.x-to-BIND 9 migration information is available in the System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP). Additional information and documentation about BIND 9 is also available on the ISC web site at http://www.isc.org. For information about IPv6 support, see the System Administration Guide: IP Services.
Google matched content |
Internal
External
http://www.securecomputing.com/index.cfm?skey=430 -- list of DNS tutorials
Internet Systems Consortium, Inc.
BIND 9 Administrator Reference Manual
Ask Mr DNS facility on the Acme site is a searchable DNS/BIND FAQ + list archive
DNS Server Setup Template for the Solaris Operating Environment
Everything Solaris/DNS for dummies
http://cramsession.brainbuzz.com/cramsession/microsoft/win2knet_infra/guide.asp
Spitzner, Lance. "DNS Access." 26 January 2000.
URL:
http://www.enteract.com/~lspitz/rules/rule6.html (21 July, 2000).
Gray, Damon. "The "IN-ADDR.ARPA" domain and it's
relation to DNS."
URL:
http://www.wednet.edu/network/whitepapers/in-addr.arpa.domain-whitepaper.html
(23 July, 2000).
DNS
HOWTO -- Nicolai Langfeldt [email protected]
HOWTO become a totally small time DNS admin.
3. A caching only name server.
7. Converting from version 4 to version 8
9. How to become a bigger time DNS admin.
Files needed on primary nameserver (Change db.mydomain.com to db.[whatever your domain is] and db.192.168.222 to db.[whatever your class C is]):
Files needed on secondary nameserver
Note that the locations and names of these files can vary quite a bit, but this naming scheme will work fine.
Index of pubdocsunix-tutorials courses
Nice collection can be found at Nominum-Resources-Standards Information-DNS RFCs
See also DNS related RFCs, DNS RFCs.
Search for RFCs is available at Internet Requests for Comments (RFC)
Major RFCs
Worth reading for zone administrators:
Reference documents about protocols and administrative rules:
Full list (from DNS related RFCs):
comp.protocols.dns.bind Last 50 Messages
comp.protocols.dns.ops Last 50 Messages
USM Engineering Department -- System Guides DNS The Domain Name Service By Glenn Stevens. Very good slides
Network Ice Corporation. "DNS Zone Transfer."
2000.
URL: http://www.netice.com/advice/intrusions/2000401
(22 July, 2000).
Mr. DNS. "Restricting zone transfers in BIND 4.9.x
with the xfernets directive."
URL: http://acmebw.com/askmrdns/00031.htm
(22 July, 2000).
Network Ice Corporation. "Split-DNS"
URL:
http://www.netice.com/advice/Services/Directory/DNS/split-DNS/default.htm (22
July, 2000).
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DNS, DHCP, IP Address Management Solutions from Men & Mice
Yahoo! - Nominum, Inc. Company Profile
Q1. FQDN stands for ________________________ ?
A: Fully Qualified Name of Domain
Q2. Which of the following is FQDN ?
a. www.mydomain.com
b. mydomain.com
c. www.mydomain.com.
A: C (the dot at the end is essential for FQDN)
Q3. True/Flase: Relative domain name (RDN) ends with the dot.
A: False
Q4. What is the maximum number of characters you can have in a FQDN ?
A: 255
Q5. True or Flase: domain names can contain the symbol "*" ?
Ans: False
Note: Only alpha numerics and dashes
Q6. _________ servers maintain the top-level zones (com, net, edu).
A: root
Q7. ___________ servers are authoritative for domains they serve.
A: Primary (Master)
Q8. The DNS server configuration file is:
A: /etc/named.conf
Q9. True/Flase: Secondary DNS servers can not be authoritative for any domains .
A: False
Note: They can be authoritative for other domains they serve
Q10. True/False: Secondary DNS Servers can help in load sharing with the primary servers .
A: True
Q11. Secondary servers are defined by the type keyword ______ in the named.conf file .
A: slave
Q12. Name 4 kinds of DNS servers ?
A: Primary, Secondary, Caching-only, Forwarding
Q13. Which 2 kinds of DNS servers can never be authoritative over any domain ?
A: Caching-only and Forwarding
Q14. You have a few PCs at the remote location. Uplink bandwidth is premium. You want to reduce DNS lookup traffic as much as possible. Which should you do ?
A: Setup a forwarding DNS server
Note: such servers build a rich DNS cache which minimize number of off-site queries (queries forwarded to master or secondary server).
Q15. 2 kinds of answers a client can get from any DNS server are:
A: Authoritative and Non-Authoritative
Q16. Non-authoritative answers can be incorrect mostly due to :
A: changes that have not been propagated via updates
Q17. What does the /var/named/named.root file specify ?
A: specifies name of address mapping of root servers
Q18. How does a DNS server find the actual root servers ?
A: by querying the servers listed in the file /var/named/named.root
Q19. Which file has name and IP for all systems in the domain (on a DNS server) ?
A: /var/named/domain.info
Q20. Which file on a DNS server has IP to name resolution ?
A: /var/named/inverse-domain.info
Q21. What does the /var/named/loopback-domain.info file specify ?
A: inverse loopback domain address
Q22. Which file does a workstation consult to find out which DNS servers should be consulted to resolve names ?
A: /etc/resolv.conf
Q23. Which command causes in.named to take a snapshot of its in-memory cached data.
A: pkill �INT in.named
Q24. You you ran pkill �INT in.named, where will it write the snapshot of its in-memory cached data ?
A: /var/named/named_dump.db
Q25. Which command causes in.named to increase its debug level by 1 ?
A: pkill �USR1 in.named
Q26. Which command causes name daemon to return to level 0 (debug) ?
A: pkill �USR2 in.named
Q27. Which command will cause the in.named daemon to reread it's configuration files ?
A: pkill �HUP in.named
Q28. True/False: DNS gives you the ability to restrict queries from machines in a particular zone.
A: True
Q29. True/False: Bind provides the facility to block unauthorized zone transfers.
A: True
Q30. Which tool converts /etc/hosts files to DNS zone files ?
A: h2n
Q31. Which DNS debugging tool allows in-depth debugging of DNS problems ?
A: dig
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War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda : SE quotes : Language Design and Programming Quotes : Random IT-related quotes : Somerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose Bierce : Bernard Shaw : Mark Twain Quotes
Bulletin:
Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 : Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law
History:
Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds : Larry Wall : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOS : Programming Languages History : PL/1 : Simula 67 : C : History of GCC development : Scripting Languages : Perl history : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history
Classic books:
The Peter Principle : Parkinson Law : 1984 : The Mythical Man-Month : How to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater�s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite
Most popular humor pages:
Manifest of the Softpanorama IT Slacker Society : Ten Commandments of the IT Slackers Society : Computer Humor Collection : BSD Logo Story : The Cuckoo's Egg : IT Slang : C++ Humor : ARE YOU A BBS ADDICT? : The Perl Purity Test : Object oriented programmers of all nations : Financial Humor : Financial Humor Bulletin, 2008 : Financial Humor Bulletin, 2010 : The Most Comprehensive Collection of Editor-related Humor : Programming Language Humor : Goldman Sachs related humor : Greenspan humor : C Humor : Scripting Humor : Real Programmers Humor : Web Humor : GPL-related Humor : OFM Humor : Politically Incorrect Humor : IDS Humor : "Linux Sucks" Humor : Russian Musical Humor : Best Russian Programmer Humor : Microsoft plans to buy Catholic Church : Richard Stallman Related Humor : Admin Humor : Perl-related Humor : Linus Torvalds Related humor : PseudoScience Related Humor : Networking Humor : Shell Humor : Financial Humor Bulletin, 2011 : Financial Humor Bulletin, 2012 : Financial Humor Bulletin, 2013 : Java Humor : Software Engineering Humor : Sun Solaris Related Humor : Education Humor : IBM Humor : Assembler-related Humor : VIM Humor : Computer Viruses Humor : Bright tomorrow is rescheduled to a day after tomorrow : Classic Computer Humor
The Last but not Least Technology is dominated by two types of people: those who understand what they do not manage and those who manage what they do not understand ~Archibald Putt. Ph.D
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Created May 16, 1996; Last modified: March 12, 2019