Redundancy is the duplication of critical components or functions of a system with the intention of increasing reliability of the system, usually in the case of a backup or fail-safe.
Questions tagged [redundancy]
461 questions
134
votes
13 answers
How to deploy an ASP.NET Application with zero downtime
To deploy a new version of our website we do the following:
Zip up the new code, and upload it to the server.
On the live server, delete all the live code from the IIS website directory.
Extract the new code zipfile into the now empty IIS…
Karl Glennon
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107
votes
1 answer
Why do we have map, fmap and liftM?
map :: (a -> b) -> [a] -> [b]
fmap :: Functor f => (a -> b) -> f a -> f b
liftM :: Monad m => (a -> b) -> m a -> m b
Why do we have three different functions that do essentially the same thing?
fredoverflow
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41
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3 answers
How to check for duplicate CSS rules?
I messed up my css and somehow i have a lot of the duplicate rules and my 1800 something lines css file is now of 3000+ lines..
Is there any way/tool that would take my css file as input and check for all the duplicate rules? and possibly generate a…
Alkshendra
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votes
6 answers
How To Check Dependencies Between Jar Files?
I recently have taken the support and programming of a web system written in JSF. The code is kind of messy and redundant, and yes, no documentation exists.
The system has over 40 jar libraries, and most of them are redundant due to old versions…
Saleh Al-Zaid
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29
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5 answers
How to reduce boilerplate currently necessary for serialization
Our software is abstracting away hardware, and we have classes that represent this hardware's state and have lots of data members for all properties of that external hardware. We need to regularly update other components about that state, and for…
sbi
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19
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2 answers
Pretty print expression with as few parentheses as possible?
My Question: What is the cleanest way to pretty print an expression without redundant parentheses?
I have the following representation of lambda expressions:
Term ::= Fun(String x, Term t)
| App(Term t1, Term t2)
| Var(String x)
By…
aioobe
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3 answers
Can CloudFlare perform automatic failover to a different backend?
I am looking for an easy way to fail over to a different DC quickly, does CloudFlare offer anything special in this regards with things like health checks or is it just like a standard DNS service?
henry.oswald
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16
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5 answers
Replication vs Redundancy
I am currently reading about Distributed Systems and I am facing two different terms which are described in a similar manner: Replication and Redundancy.
Can anyone explain each term in part?
Dina Bogdan
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16
votes
7 answers
CSS "Normalizer" tool?
I need to maintain & improve an existing website and I am drowning in the redundancy I have discovered in its CSS stylesheet. Given the existing redundancy and non-methodlogical ordering of elements, it's hard to track and predict how a minor change…
Android Eve
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15
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7 answers
Database normalization - who's right?
My professor (who claimed to have a firm understanding about systems development for many years) and I are arguing about the design of our database.
As an example:
My professor insists this design is right:
(list of…
Arman
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12
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3 answers
Sessions Failover with PHP-memcache against memcached
Colleagues!
I'm running php 5.3 (5.3.8) with memcache (2.2.6) client library (http://pecl.php.net/package/memcache) to deal with memcached server.
My goal is to have failover solution for sessions engine, namely:
Only native php sessions support…
Eugene
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11
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3 answers
Cross-colo fail-over design, DNS level fail-over?
I'm interested in cross-colo fail-over strategies for web applications, such that if the main site fails users seamlessly land at the fail-over site in another colo.
The application side of things looks to be mostly figured out with a master-slave…
Parand
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11
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1 answer
small code redundancy within while-loops (doesn't feel clean)
So, in Python (though I think it can be applied to many languages), I find myself with something like this quite often:
the_input = raw_input("what to print?\n")
while the_input != "quit":
print the_input
the_input = raw_input("what to…
Ponkadoodle
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10
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4 answers
How can I merge two redundant records in a MySQL table, maintaining all PK/FK relationships?
Say I have a table customers with the following fields and records:
id first_name last_name email phone
------------------------------------------------------------------------
1 Michael Turley …
Mike Turley
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10
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Remove duplicated elements from list
I have a list of character vectors:
my.list <- list(e1 = c("a","b","c","k"),e2 = c("b","d","e"),e3 = c("t","d","g","a","f"))
And I'm looking for a function that for any character that appears more than once across the list's vectors (in each vector…
dan
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