Here’s a iOS 11.2.1 IPSW download link for iPhone, iPad or iPod touch. With iOS 11.2.1 ipsw download, you can restore or update your iPhone/iPad manually via iTunes.

iOS 11.2.1 with a small fix update for iPhone, iPad or iPod touch which basically fixes the HomeKit accessories in Home app and auto focus bug on iPhone X and iPhone 8.

Here's a iOS 11.2.1 IPSW download link for iPhone, iPad or iPod touch. With iOS 11.2.1 ipsw download, you can restore or update your iPhone/iPad manually via iTunes.
Download iOS 11.2.1 IPSW for iPhone:

iOS 11.2.1 (iPhone 5s GSM): iPhone_4.0_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 5s GSM+CDMA): iPhone_4.0_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 6 Plus): iPhone_5.5_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 6): iPhone_4.7_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 6s): iPhone_4.7_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 6s Plus): iPhone_5.5_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone SE): iPhone_4.0_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 7 GSM+CDMA): iPhone_4.7_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 7 Plus GSM+CDMA): iPhone_5.5_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 7 GSM): iPhone_4.7_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 7 Plus GSM): iPhone_5.5_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 8 GSM+CDMA): iPhone_4.7_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 8 Plus GSM+CDMA): iPhone_5.5_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 8 GSM): iPhone_4.7_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone 8 Plus GSM): iPhone_5.5_P3_11.0_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone X GSM+CDMA): iPhone10,6_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPhone X GSM): iPhone10,6_11.2.1_15C153_Restore.ipsw

Download iOS 11.2.1 IPSW for iPad:

iOS 11.2.1 (iPad Air Wi-Fi): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Air Cellular): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 2 Wi-Fi): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 2 Cellular): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Air China): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 2 China): iPad_64bit_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 3 Wi-Fi): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 3 Cellular): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 3 China): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Air 2 Wi-Fi): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Air 2 Cellular): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 4 Wi-Fi): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Mini 4 Cellular): iPad_64bit_TouchID_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro Wi-Fi): iPadPro_12.9_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro Cellular): iPadPro_12.9_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 9.7 Wi-Fi): iPadPro_9.7_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 9.7 Cellular): iPadPro_9.7_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad 5 Wi-Fi): iPad_64bit_TouchID_ASTC_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad 5 Cellular): iPad_64bit_TouchID_ASTC_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 12.9 Wi-Fi 2nd Gen): iPad_Pro_HFR_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 12.9 Cellular 2nd Gen): iPad_Pro_HFR_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 10.5 Wi-Fi): iPad_Pro_HFR_11.2.1_15C153_Restore.ipsw
iOS 11.2.1 (iPad Pro 10.5 Cellular): iPad_Pro_HFR_11.2.1_15C153_Restore.ipsw

Download iOS 11.2.1 IPSW for iPod Touch:

iOS 11.2.1 (6G): iPodtouch_11.2.1_15C153_Restore.ipsw