diff --git a/package/frr/Config.in b/package/frr/Config.in
index 0afd8c61a2..c26b160b2a 100644
--- a/package/frr/Config.in
+++ b/package/frr/Config.in
@@ -1,15 +1,19 @@
 config BR2_PACKAGE_FRR
 	bool "frr"
-	depends on BR2_TOOLCHAIN_HAS_THREADS
+	depends on BR2_TOOLCHAIN_HAS_THREADS # protobuf-c
 	depends on !BR2_STATIC_LIBS # libyang
 	depends on BR2_USE_MMU # fork()
 	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # json-c, libyang
+	depends on BR2_INSTALL_LIBSTDCPP # protobuf-c
+	depends on BR2_PACKAGE_HOST_PROTOBUF_ARCH_SUPPORTS # protobuf-c
+	depends on BR2_HOST_GCC_AT_LEAST_7 # protobuf-c
 	select BR2_PACKAGE_BASH
 	select BR2_PACKAGE_BUSYBOX_SHOW_OTHERS # bash
 	select BR2_PACKAGE_LIBXCRYPT if BR2_TOOLCHAIN_USES_GLIBC
 	select BR2_PACKAGE_LIBYANG
 	select BR2_PACKAGE_READLINE
 	select BR2_PACKAGE_JSON_C
+	select BR2_PACKAGE_PROTOBUF_C
 	help
 	  The FRRouting Protocol Suite.
 
@@ -34,7 +38,9 @@ config BR2_PACKAGE_FRR_NHRPD
 
 endif
 
-comment "frr needs a toolchain w/ threads, dynamic library"
+comment "frr needs a toolchain w/ threads, dynamic library, C++, host gcc >= 7"
+	depends on BR2_PACKAGE_HOST_PROTOBUF_ARCH_SUPPORTS
 	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_USE_MMU
-	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS
+	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS || \
+		!BR2_INSTALL_LIBSTDCPP || !BR2_HOST_GCC_AT_LEAST_7
diff --git a/package/frr/frr.hash b/package/frr/frr.hash
index 4a61084bae..81f8dfdae3 100644
--- a/package/frr/frr.hash
+++ b/package/frr/frr.hash
@@ -1,3 +1,11 @@
 # Locally calculated
-sha256  7ae9d8bafc65bb5d0f21061ac61dbc6cf93b2b05a5dae9e5eec72ed42388551e  frr-8.5.4.tar.gz
-sha256  8177f97513213526df2cf6184d8ff986c675afb514d4e68a404010521b880643  COPYING
+sha256  6eb254c72dca867fefffd5ded80a6c2d5ce8df223ce93263302db4b8bfbb19c4  frr-9.1.1.tar.gz
+sha256  7bf053957d6c38e39a06a112c60ff35b228d3bd03edbe8c9a03508b051128d16  COPYING
+sha256  f9e0c21faf738da586281c0beaad3cd56204c19085a10fe05e4d3d7f8b5863d2  doc/licenses/BSD-2-Clause
+sha256  aca297b8fd3a43e3bb200f1e2e043c0db6c897325f5ff7f23f7530302a6bf713  doc/licenses/BSD-3-Clause
+sha256  8177f97513213526df2cf6184d8ff986c675afb514d4e68a404010521b880643  doc/licenses/GPL-2.0
+sha256  6d80da3224cbdcf016ea554e00fc9cd933bd1a3417cb5e5b7abf59f6d126761d  doc/licenses/ISC
+sha256  dc626520dcd53a22f727af3ee42c770e56c97a64fe3adb063799d8ab032fe551  doc/licenses/LGPL-2.1
+sha256  2a1124bf8bc60f1f59b67e15e3d261b5d60fcd9674a3eace0a5502fd4287d528  doc/licenses/LicenseRef-Skiplist-BSD-0-Clause
+sha256  074415b57c6ba1780483d89e55f40dec3ded96c28aaf47d63c486683ba553e7c  doc/licenses/MIT
+sha256  b5065838cbac452dfc855ba6e6e031481ad2c68406f70d21ead9321374653e6c  doc/licenses/Unlicense
diff --git a/package/frr/frr.mk b/package/frr/frr.mk
index 1b7d66fc68..7f26fd3c57 100644
--- a/package/frr/frr.mk
+++ b/package/frr/frr.mk
@@ -4,15 +4,28 @@
 #
 ################################################################################
 
-FRR_VERSION = 8.5.4
+FRR_VERSION = 9.1.1
 FRR_SITE = $(call github,FRRouting,frr,frr-$(FRR_VERSION))
-FRR_LICENSE = GPL-2.0
-FRR_LICENSE_FILES = COPYING
+FRR_LICENSE = GPL-2.0+
+FRR_LICENSE_FILES = \
+	COPYING \
+	doc/licenses/BSD-2-Clause \
+	doc/licenses/BSD-3-Clause \
+	doc/licenses/GPL-2.0 \
+	doc/licenses/ISC \
+	doc/licenses/LGPL-2.1 \
+	doc/licenses/LicenseRef-Skiplist-BSD-0-Clause \
+	doc/licenses/MIT \
+	doc/licenses/Unlicense
+# tools/gcc-plugins/frr-format.[ch] is not enabled by frr's ./configure, so gcc's
+# GPLv3 does not apply
+#	doc/licenses/GPL-3.0
 FRR_CPE_ID_VENDOR = linuxfoundation
 FRR_CPE_ID_PRODUCT = free_range_routing
 FRR_AUTORECONF = YES
 
 FRR_DEPENDENCIES = host-frr readline json-c libyang \
+	protobuf-c \
 	$(if $(BR2_PACKAGE_C_ARES),c-ares) \
 	$(if $(BR2_PACKAGE_LIBXCRYPT),libxcrypt)
 
@@ -22,6 +35,8 @@ FRR_CONF_ENV = \
 	ac_cv_lib_cunit_CU_initialize_registry=no \
 	CFLAGS="$(TARGET_CFLAGS) -DFRR_XREF_NO_NOTE"
 
+# Do not enable -fplugin=frr-format for production, see doc/developer/workflow.rst,
+# it is only intended for FRR's developments
 FRR_CONF_OPTS = --with-clippy=$(HOST_DIR)/bin/clippy \
 	--sysconfdir=/etc/frr \
 	--localstatedir=/var/run/frr \