I have a few comments for you. I will leave the dereferencing code out of my response because my main points have to do with the regex matching part and also I don't really understand what you are doing with your deref of a reference to a scalar.

First I would not match against the whole comma separated line, I would narrow the focus to the field that you are interested in. Below I use a split to get field[1]. Another poster suggested using a boundary condition in the regex for the same intended purpose (making sure you are matching against what you think that you are). We don't know what those other names or id's in the line look like, perhaps one server is "sms1Master" or whatever.

Instead of multiple "or" terms, I would use a character set in this case. This makes it easier for me to see what is going to match or not match. Of course mileage varies.

use strict;
use warnings;

while (<DATA>)
{
    my $SMSfield = (split(',',$_))[1];
    
    if ($SMSfield =~ /SMS[1HI]/i)
    {
       print "Match $SMSfield\n";
    }
    else
    {
       print "No Match $SMSfield\n";
    }  
}   

=prints
Match SMS1
Match SMSh
Match SMSH
Match SMSi
Match SMSI
Match SmsI  **Note this match** I think in your case, this is fine.
No Match SMSx
=cut

__DATA__
SMS,SMS1,20190811,084500,servname,servid,servname1,s1,400,300,300,300,
+300,300
SMS,SMSh,20190811,084500,servname,servid,servname1,s1,700,300,300,300,
+300,300
SMS,SMSH,20190811,084500,servname,servid,servname1,s1,600,300,300,300,
+300,300
SMS,SMSi,20190811,084500,servname,servid,servname1,s1,800,300,300,300,
+300,300
SMS,SMSI,20190811,084500,servname,servid,servname1,s1,500,300,300,300,
+300,300
SMS,SmsI,20190811,084500,servname,servid,servname1,s1,500,300,300,300,
+300,300
SMS,SMSx,20190811,084500,servname,servid,servname1,s1,500,300,300,300,
+300,300
[download]

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