Update.

RouterOS_String_Generator.rsc

@@ -0,0 +1,45 @@
+# RouterOS Function
+# Copyright (c) Grzegorz Budny 
+# Generates random string based on dictionary of six chars length
+
+:global GenerateString do={
+
+    :global generatedString; 
+    
+    :local characters q,w,e,r,t,y,u,i,o,p,l,k,j,h,g,f,1,2,3,4,5,6,7,8,9,0,d,s,a,z,x,c,v,b,n,m,M,N,B,V,C,X,Z,A,S,D,F,G,H,J,K,L,P,O,I,U,Y,T,R,E,W,Q;
+      
+    :local hour [:pick [/system clock get time] 0 2];
+    :local minute [:pick [/system clock get time] 3 5];
+    :local second [:pick [/system clock get time] 6 8];
+
+    :if ((:pick $hour 0) = 0) do={
+
+        :set $hour [:pick $hour 1]; 
+
+    }
+    :if ((:pick $minute 3) = 0) do={
+
+        :set $minute [:pick $minute 4];
+        
+    }
+    :if ((:pick $second 6) = 0) do={
+
+        :set $second [:pick $second 7];
+        
+    }\
+    else={
+
+        :log warning "Something's wrong with system time. Check system time and NTP settings.";
+
+    }
+
+    :set $generatedString ($generatedString.([:pick $characters $hour].[:pick $characters $minute].[:pick $characters $second].\
+    [:pick $characters ($hour/2)].[:pick $characters ($minute/2)].[:pick $characters ($second/2)]));
+    
+    :log info "...:::Random string generated:::..."
+
+    :return ($generatedString);
+    
+}
+
+$GenerateString;