It is reported about Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) and Sayyiduna Abdullah bin Umar that they both said: The Prophet (peace and blessings be upon him) established the prayer while travelling as two rak'ahs, and they are complete; and performing the witr while travelling is a Sunnah. (Allamah al-Haythami says:) I say: Part of it is reported in the Sahih.
Al-Bazzar recorded it; its chain contains a narrator, Jabir al-Ju'fi, whom Shu'bah and al-Thawri graded thiqah (trustworthy), while others graded him da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2939
Hadith Gradingمحدثین:إسنادہ ضعیف، جابر الجعفی جمہور کے نزدیک ضعیف ہونے کی وجہ سے سند ضعیف ہے۔