I have gone through DTAA between India & Germany. AS per this it is saying exempted.
ARTICLE 11 - Interest - 1. Interest arising in a Contracting State and paid to a resident of the other Contracting State may be taxed in that other State. 2. However, such interest may also be taxed in Contracting State in which it arises and according to the laws of that State, but if the recipient is the beneficial owner of the interest the tax so charged shall not exceed 10 per cent of the gross amount of the interest. 3. Notwithstanding the provisions of paragraphs 1 and 2 (a) interest arising in the Federal Republic of Germany and paid to the Government of the Republic of India, the Reserve Bank of India, the Industrial Finance Corporation of India, the Industrial Development Bank of India, the Export-Import Bank of India, National Housing Bank and Small Industries Development Bank of India shall be exempt from German tax; (b) interest arising in the Republic of India and paid to the Government of the Federal Republic of Germany, the Deutsche Bundesbank, the Kreditanstat fur Wiederaufbau or the Deutsche Investitions-und Entwicklungsgesellschaft (DEG) and interest paid in consideration of a loan guaranteed by HERMES-Deckung shall be exempt from Indian tax.