Answer
(Fatwa: 270/245=D/1430)
(1) It is sunnah to do musafaha with two hands. However, it is proved to do it with right hand only. Doing musafaha with two hands is proved from the hadith of Sahih Bukhari 2:926.
(2) Musafaha is sunnah when one meets other, also at the time of departure:
كان رسول اللَّهِ صلی اللہ علیہ وسلم إذا وَدَّعَ رَجُلًا أَخَذَ بيده فلا يَدَعُهَا حتى يَكُونَ الرَّجُلُ هو يَدَعُ يَدَ النبي صلی اللہ علیہ وسلم وَيَقُولُ: أستودع اللَّهَ دِينَكَ وَأَمَانَتَكَ وَآخِرَ عَمَلِكَ (Tirmizi and Abu Dawood)
Greeting with salam is sunnah at the time of meeting and departure according to Mishkwat, chapter Salam.
(3) This is mentioned in Zadul Ma?ad 2:629 about the Christians of Najran.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband