You need numerical sort, try the following

for $key ( sort {$a<=>$b} keys %hash) {
           print "($key)->($hash{$key})\n";
}
[download]

In your way with foreach

foreach (sort { $a <=> $b } keys(%SRV) )
{
    print"$_: "."$SRV{$_}";
}
[download]

foreach code added

Thanks Vinoth, that was quick and my silly thing resolved. Everyone is so awesome here..

Do you understand why that worked? If not, have you looked it up in the documentation?

The way forward always starts with a minimal test.

In the Tutorials section, you will find A brief tutorial on Perl's native sorting facilities.

The following link is indirectly accessible via the link given above, but it's a bit deeply buried there and I want to bring it above the fold because it's such a good article: A Fresh Look at Efficient Perl Sorting.

---

Give a man a fish:  <%-{-{-{-<

I don't know how you populate your hash, but you wouldn't need to sort at all if you used an array instead:

my @SRV = (
  'zumen530n.pdg.duranto.com',
  'zumen531n.pdg.duranto.com',
  'zumen532n.pdg.duranto.com', # etc
);
print "$_ $SRV[ $_ ]\n" for 0 .. $#SRV;
[download]

Of course, this prints 0-20 instead of 1-21, but that's easy to fix if it's important.

Update: In fact, whenever I see a hash like:

my %h = (
  1 => 'foo',
  2 => 'bar',
  3 => 'baz',
  4 => 'quux',
);
[download]

I always consider whether it wouldn't be better to use a simple array.

Going along with Not_a_Number, there are also many ordered hash implementations such as Hash::Ordered and Tie::IxHash when alpha-numeric keys are desired.

Hey, let’s just make things a little easier for the next Gentle Reader, and actually explain things:

In the statement:   sort { $a <=> $b } keys %hash)

... the part in bold underline is the Magick:   an in-line sort comparison subroutine (which always takes two arguments/variables, always named $a and $b).   This is used here in order that the numeric comparison operator (<=>) can be specified, instead of sort’s default, which is to use the string comparison operator (cmp).

If you glance at the output in the original post, you will see that the sort keys are “sorted correctly” ... as strings, not as numbers.   (The “default” sorting behavior, in other words, is equivalent to:   sort { $a cmp $b } ...)

Q.E.D.

P.S.   This is one of the counter-intuitive features of Perl.   Ordinarily, you might expect that there would be one comparison-operator which would “know” whether the values being passed are numeric or string.   (As the ordinary “less-than, greater-than” relational operators do.)   But this, actually, is a feature of the language that is specifically designed for use in sorting.   The language, by default, consistently treats its sort-keys as strings, no matter what is their internal data-type at the moment, and yet makes it very easy ... as just demonstrated ... to compare them numerically.)