Sunan an-Nasa'i 3167
It was narrated from Salman Al-Khair that the Messenger of Allah (ﷺ) said:
"Whoever guards Ribat (the frontier) for one day and one night, will be given a reward like that for fasting and praying Qiyam for a month, and whoever dies at Ribat (guarding the frontier) will be rewarded, and he will be given provision, and he will be kept safe from Al-Fattan." [1]

[1] According to As-Sindi, the preferred pronunciation is Al-Fattan, plural of Fatan refering to Al-Munkar and An-Nakir, while Al-Fattan would refer to Ash-Shaitan or the like, among the punishment of the grave, or, the angels of chastisement.
قَالَ الْحَارِثُ بْنُ مِسْكِينٍ قِرَاءَةً عَلَيْهِ وَأَنَا أَسْمَعُ، عَنِ ابْنِ وَهْبٍ، أَخْبَرَنِي عَبْدُ الرَّحْمَنِ بْنُ شُرَيْحٍ، عَنْ عَبْدِ الْكَرِيمِ بْنِ الْحَارِثِ، عَنْ أَبِي عُبَيْدَةَ بْنِ عُقْبَةَ، عَنْ شُرَحْبِيلَ بْنِ السِّمْطِ، عَنْ سَلْمَانَ الْخَيْرِ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ ‏
"‏ مَنْ رَابَطَ يَوْمًا وَلَيْلَةً فِي سَبِيلِ اللَّهِ كَانَ لَهُ كَأَجْرِ صِيَامِ شَهْرٍ وَقِيَامِهِ وَمَنْ مَاتَ مُرَابِطًا أُجْرِيَ لَهُ مِثْلُ ذَلِكَ مِنَ الأَجْرِ وَأُجْرِيَ عَلَيْهِ الرِّزْقُ وَأَمِنَ مِنَ الْفَتَّانِ ‏"‏ ‏.‏