Bismillaah:

The Prophet صلي الله عليه وسلم said:

"You shall not enter Paradise until you believe, and you have not believed until you love one another. Shall I tell you of something you can do to make you love one another? Spread the greetings of Salam [ peace ] amongst yourselves.

Takhreej:

{ Imam Muslim in his Saheeh 1/74 }

Amaar رضي الله عنه said:

There are three things which whoever gathers all of them together, then he has gathered Iman ...greeting people with greetings of Salam."

Takhreej:

{ Imam Al Bukhari in his Saheeh }

However, from among the tribulations that afflicted the Muslims in this age

The Prophet صلي الله عليه وسلم said,

'' Verily, just before the Hour, greetings of peace [ salaam ] will be exclusive to those known or to people of status [only]''

Takhreej:

{ Imam Ahmad in his Musnad #387 and Shaykh Al Albaani said, " This chain is Saheeh upon the conditions of Bukhari and Muslim }

This practise is so widespread amoung Muslims in these times that a Man or woman would initiate salaam to those close to him, or Country of origin only totally avoiding others, or even worst, walk by another Muslim without saying anything. This is a clear violation of the Prophet صلي الله عليه وسلم teaching and that is to give Salaam ''both to those you know and to those you do not know''

***And Allaah عزوجل knows best ***