BPI R4 nf_conntrack_helper

My device is BPI R4 an I used the firmware downloaded from OpenWrt Firmware Selector and found that I could not connect to the pptp client via the pptp server. I can’t find net.netfilter.nf_conntrack_helper in my system, can anyone help me with this problem?
These are my system info

root@OpenWrt:/# sysctl -w net.netfilter.nf_conntrack_helper=1
sysctl: error: 'net.netfilter.nf_conntrack_helper' is an unknown key
root@OpenWrt:/# opkg list | grep helper
kmod-nf-nathelper - 6.1.81-1
kmod-nf-nathelper-extra - 6.1.81-1
root@OpenWrt:/# cat /etc/op
openwrt_release  openwrt_version  opkg.conf        opkg/
root@OpenWrt:/# cat /etc/openwrt_release 
DISTRIB_ID='OpenWrt'
DISTRIB_RELEASE='SNAPSHOT'
DISTRIB_REVISION='r25529-1d3d6ef826'
DISTRIB_TARGET='mediatek/filogic'
DISTRIB_ARCH='aarch64_cortex-a53'
DISTRIB_DESCRIPTION='OpenWrt SNAPSHOT r25529-1d3d6ef826'
DISTRIB_TAINTS=''
root@OpenWrt:/# cat /etc/openwrt_version 
r25529-1d3d6ef826
root@OpenWrt:/# cat /etc/openwrt_
openwrt_release  openwrt_version
root@OpenWrt:/# cat /etc/openwrt_
openwrt_release  openwrt_version
root@OpenWrt:/# cat /etc/op
openwrt_release  openwrt_version  opkg.conf        opkg/
root@OpenWrt:/# cat /etc/o
odhcp6c.user     openwrt_release  opkg.conf        os-release
odhcp6c.user.d/  openwrt_version  opkg/
root@OpenWrt:/# cat /etc/
TZ                    hotplug.json          profile.d/
banner                init.d/               protocols
banner.failsafe       inittab               rc.button/
board.d/              iproute2/             rc.common
board.json            localtime             rc.d/
capabilities/         luci-uploads/         rc.local
chatscripts/          modules-boot.d/       resolv.conf
config/               modules.conf          services
crontabs/             modules.d/            shadow
dbus-1/               mtab                  shells
device_info           nftables.d/           shinit
diag.sh               odhcp6c.user          ssl/
dnsmasq.conf          odhcp6c.user.d/       sysctl.conf
dropbear/             openwrt_release       sysctl.d/
e2fsck.conf           openwrt_version       syslog.conf
ethers                opkg.conf             sysupgrade.conf
fstab                 opkg/                 uci-defaults/
fw_env.config         os-release            udhcpc.user
gcom/                 passwd                udhcpc.user.d/
group                 ppp/                  urandom.seed
hosts                 pptpd.conf            usb-mode.json
hotplug-preinit.json  preinit               xattr.conf
hotplug.d/            profile
root@OpenWrt:/# cat /etc/os-release 
NAME="OpenWrt"
VERSION="SNAPSHOT"
ID="openwrt"
ID_LIKE="lede openwrt"
PRETTY_NAME="OpenWrt SNAPSHOT"
VERSION_ID="snapshot"
HOME_URL="https://openwrt.org/"
BUG_URL="https://bugs.openwrt.org/"
SUPPORT_URL="https://forum.openwrt.org/"
BUILD_ID="r25529-1d3d6ef826"
OPENWRT_BOARD="mediatek/filogic"
OPENWRT_ARCH="aarch64_cortex-a53"
OPENWRT_TAINTS=""
OPENWRT_DEVICE_MANUFACTURER="OpenWrt"
OPENWRT_DEVICE_MANUFACTURER_URL="https://openwrt.org/"
OPENWRT_DEVICE_PRODUCT="Generic"
OPENWRT_DEVICE_REVISION="v0"
OPENWRT_RELEASE="OpenWrt SNAPSHOT r25529-1d3d6ef826"
root@OpenWrt:/# cat /etc/openwrt_version 
r25529-1d3d6ef826
root@OpenWrt:/# cat /etc/openwrt_release 
DISTRIB_ID='OpenWrt'
DISTRIB_RELEASE='SNAPSHOT'
DISTRIB_REVISION='r25529-1d3d6ef826'
DISTRIB_TARGET='mediatek/filogic'
DISTRIB_ARCH='aarch64_cortex-a53'
DISTRIB_DESCRIPTION='OpenWrt SNAPSHOT r25529-1d3d6ef826'
DISTRIB_TAINTS=''
root@OpenWrt:/# sysctl -w net.netfilter.nf_conntrack_helper=1
sysctl: error: 'net.netfilter.nf_conntrack_helper' is an unknown key
root@OpenWrt:/# sysctl -w net.netfilter.nf_conntrack_helper=1^C

root@OpenWrt:/# ^C

root@OpenWrt:/# cat /proc/sys/net/netfilter/nf_conntrack_helper
cat: can't open '/proc/sys/net/netfilter/nf_conntrack_helper': No such file or directory
root@OpenWrt:/# lsmod 
af_alg                 28672  4 algif_skcipher,algif_rng,algif_hash,algif_aead
algif_aead             16384  0 
algif_hash             16384  0 
algif_rng              16384  0 
algif_skcipher         16384  0 
aquantia               28672  0 
arc4                   16384  0 
asn1_decoder           16384  1 nf_nat_snmp_basic
at24                   20480  0 
atm                    53248  3 usbatm,pppoatm,br2684
authenc                16384  2 crypto_safexcel,authencesn
authencesn             16384  0 
br2684                 24576  0 
cdc_acm                32768  0 
cdc_eem                16384  0 
cdc_ether              16384  2 rndis_host,cdc_ncm
cdc_mbim               16384  0 
cdc_ncm                24576  1 cdc_mbim
cdc_subset             16384  0 
cdc_wdm                28672  3 cdc_mbim,qmi_wwan
cfg80211              307200  5 mt7996e,mt7915e,mt76_connac_lib,mt76,mac80211
compat                 16384  2 mac80211,cfg80211
crypto_safexcel       122880  0 
crypto_user            16384  0 
des_generic            16384  0 
ehci_fsl               16384  0 
ehci_hcd               61440  3 ehci_pci,ehci_platform,ehci_fsl
ehci_pci               16384  0 
ehci_platform          16384  0 
evdev                  28672  0 
fsl_mph_dr_of          16384  0 
gpio_button_hotplug    16384  0 
gre                    16384  2 pptp,ip_gre
hid                   118784  2 usbhid,hid_generic
hid_generic            16384  0 
hso                    45056  0 
i2c_mux                16384  1 i2c_mux_pca954x
i2c_mux_pca954x        16384  0 
input_core             49152  2 hid,evdev
ip_gre                 28672  0 
ip_tables              28672  4 iptable_nat,iptable_raw,iptable_mangle,iptable_filter
ip_tunnel              28672  1 ip_gre
ip6_tables             28672  3 ip6table_raw,ip6table_mangle,ip6table_filter
ip6t_REJECT            16384  0 
ip6table_filter        16384  0 
ip6table_mangle        16384  0 
ip6table_raw           16384  0 
ipt_REJECT             16384  0 
iptable_filter         16384  0 
iptable_mangle         16384  0 
iptable_nat            16384  0 
iptable_raw            16384  0 
leds_gpio              16384  0 
libcrc32c              16384  1 nf_tables
libdes                 24576  2 crypto_safexcel,des_generic
mac80211              593920  4 mt7996e,mt7915e,mt76_connac_lib,mt76
md5                    16384  1 crypto_safexcel
mdio_i2c               16384  1 sfp
mhi                    73728  2 mhi_wwan_mbim,mhi_wwan_ctrl
mhi_wwan_ctrl          16384  0 
mhi_wwan_mbim          20480  0 
mii                    16384  1 usbnet
mt76                   77824  3 mt7996e,mt7915e,mt76_connac_lib
mt76_connac_lib        53248  2 mt7996e,mt7915e
mt7915e               143360  0 
mt7996e               122880  0 
nf_conncount           24576  1 xt_connlimit
nf_conntrack           90112 36 xt_connlimit,nf_conncount,xt_state,xt_nat,xt_helper,xt_conntrack,xt_connmark,xt_connbytes,xt_REDIRECT,xt_NETMAP,xt_MASQUERADE,xt_CT,nft_redir,nft_nat,nft_masq,nft_flow_offload,nft_ct,nf_nat_tftp,nf_nat_snmp_basic,nf_nat_sip,nf_nat_pptp,nf_nat_irc,nf_nat_h323,nf_nat_ftp,nf_nat_amanda,nf_nat,nf_flow_table,nf_conntrack_tftp,nf_conntrack_snmp,nf_conntrack_sip,nf_conntrack_pptp,nf_conntrack_irc,nf_conntrack_h323,nf_conntrack_ftp,nf_conntrack_broadcast,nf_conntrack_amanda
nf_conntrack_amanda    16384  3 nf_nat_amanda
nf_conntrack_broadcast   16384  1 nf_conntrack_snmp
nf_conntrack_ftp       16384  3 nf_nat_ftp
nf_conntrack_h323      49152  5 nf_nat_h323
nf_conntrack_irc       16384  2 nf_nat_irc
nf_conntrack_pptp      16384  2 nf_nat_pptp
nf_conntrack_sip       32768  3 nf_nat_sip
nf_conntrack_snmp      16384  2 nf_nat_snmp_basic
nf_conntrack_tftp      16384  3 nf_nat_tftp
nf_defrag_ipv4         16384  1 nf_conntrack
nf_defrag_ipv6         20480  1 nf_conntrack
nf_flow_table          32768  2 nf_flow_table_inet,nft_flow_offload
nf_flow_table_inet     16384  0 
nf_log_syslog          20480  0 
nf_nat                 40960 16 iptable_nat,xt_nat,xt_REDIRECT,xt_NETMAP,xt_MASQUERADE,nft_redir,nft_nat,nft_masq,nft_chain_nat,nf_nat_tftp,nf_nat_sip,nf_nat_pptp,nf_nat_irc,nf_nat_h323,nf_nat_ftp,nf_nat_amanda
nf_nat_amanda          16384  0 
nf_nat_ftp             16384  0 
nf_nat_h323            16384  0 
nf_nat_irc             16384  0 
nf_nat_pptp            16384  0 
nf_nat_sip             20480  0 
nf_nat_snmp_basic      16384  0 
nf_nat_tftp            16384  0 
nf_reject_ipv4         16384  3 nft_reject_ipv4,nft_reject_inet,ipt_REJECT
nf_reject_ipv6         16384  3 nft_reject_ipv6,nft_reject_inet,ip6t_REJECT
nf_tables             176128251 nft_fib_inet,nf_flow_table_inet,nft_reject_ipv6,nft_reject_ipv4,nft_reject_inet,nft_reject,nft_redir,nft_quota,nft_objref,nft_numgen,nft_nat,nft_masq,nft_log,nft_limit,nft_hash,nft_flow_offload,nft_fib_ipv6,nft_fib_ipv4,nft_fib,nft_ct,nft_chain_nat
nfnetlink              20480  1 nf_tables
nft_chain_nat          16384  2 
nft_ct                 20480 13 
nft_fib                16384  3 nft_fib_inet,nft_fib_ipv6,nft_fib_ipv4
nft_fib_inet           16384  0 
nft_fib_ipv4           16384  1 nft_fib_inet
nft_fib_ipv6           16384  1 nft_fib_inet
nft_flow_offload       16384  0 
nft_hash               16384  0 
nft_limit              16384  5 
nft_log                16384  0 
nft_masq               16384  1 
nft_nat                16384  0 
nft_numgen             16384  0 
nft_objref             16384  9 
nft_quota              16384  0 
nft_redir              16384  0 
nft_reject             16384  3 nft_reject_ipv6,nft_reject_ipv4,nft_reject_inet
nft_reject_inet        16384  2 
nft_reject_ipv4        16384  0 
nft_reject_ipv6        16384  0 
ohci_hcd               49152  1 ohci_platform
ohci_platform          16384  0 
option                 61440  1 
ppp_async              24576  0 
ppp_generic            45056  6 pppoe,pptp,pppox,ppp_mppe,ppp_async,pppoatm
ppp_mppe               16384  0 
pppoatm                20480  0 
pppoe                  24576  0 
pppox                  20480  2 pppoe,pptp
pptp                   32768  0 
pwm_fan                16384  0 
qcserial               20480  0 
qmi_wwan               32768  0 
rndis_host             16384  0 
rtc_pcf8563            20480  0 
seqiv                  16384  0 
sfp                    32768  0 
sha1_ce                16384  0 
sha1_generic           16384  2 crypto_safexcel,sha1_ce
sha512_arm64           20480  0 
slhc                   16384  1 ppp_generic
ts_bm                  16384  0 
ts_fsm                 16384  0 
ts_kmp                 16384  6 
uhci_hcd               36864  0 
usb_common             16384  6 xhci_plat_hcd,xhci_hcd,ohci_platform,ohci_hcd,ehci_platform,usbcore
usb_wwan               24576  2 qcserial,option
usbatm                 28672  0 
usbcore               196608 29 qcserial,option,cdc_mbim,usb_wwan,rndis_host,qmi_wwan,cdc_subset,cdc_ncm,cdc_ether,cdc_eem,usbserial,usbnet,usbhid,usbatm,hso,cdc_wdm,cdc_acm,xhci_plat_hcd,xhci_pci,xhci_mtk_hcd,xhci_hcd,uhci_hcd,ohci_platform,ohci_hcd,ehci_pci,ehci_platform,ehci_fsl,ehci_hcd
usbhid                 40960  0 
usbnet                 32768  7 cdc_mbim,rndis_host,qmi_wwan,cdc_subset,cdc_ncm,cdc_ether,cdc_eem
usbserial              32768  5 qcserial,option,usb_wwan
wwan                   24576  2 mhi_wwan_mbim,mhi_wwan_ctrl
x_tables               32768 37 xt_connlimit,iptable_nat,xt_state,xt_nat,xt_helper,xt_conntrack,xt_connmark,xt_connbytes,xt_REDIRECT,xt_NETMAP,xt_MASQUERADE,xt_CT,ipt_REJECT,xt_time,xt_tcpudp,xt_recent,xt_quota,xt_pkttype,xt_owner,xt_multiport,xt_mark,xt_mac,xt_limit,xt_comment,xt_cgroup,xt_addrtype,xt_TCPMSS,xt_LOG,iptable_raw,iptable_mangle,iptable_filter,ip6table_raw,ip_tables,ip6table_mangle,ip6table_filter,ip6_tables,ip6t_REJECT
xhci_hcd              143360  3 xhci_plat_hcd,xhci_pci,xhci_mtk_hcd
xhci_mtk_hcd           24576  0 
xhci_pci               20480  0 
xhci_plat_hcd          16384  0 
xt_CT                  16384  0 
xt_LOG                 16384  0 
xt_MASQUERADE          16384  0 
xt_NETMAP              16384  0 
xt_REDIRECT            16384  0 
xt_TCPMSS              16384  0 
xt_addrtype            16384  0 
xt_cgroup              16384  0 
xt_comment             16384  0 
xt_connbytes           16384  0 
xt_connlimit           16384  0 
xt_connmark            16384  0 
xt_conntrack           16384  0 
xt_helper              16384  0 
xt_limit               16384  0 
xt_mac                 16384  0 
xt_mark                16384  0 
xt_multiport           16384  0 
xt_nat                 16384  0 
xt_owner               16384  0 
xt_pkttype             16384  0 
xt_quota               16384  0 
xt_recent              24576  0 
xt_state               16384  0 
xt_tcpudp              16384  0 
xt_time                16384  0 
root@OpenWrt:/# opkg list | grep helper
kmod-nf-nathelper - 6.1.81-1
kmod-nf-nathelper-extra - 6.1.81-1

It can be found 4 times with 4 errors.
No idea why. Did you Customize installed packages and/or first boot script?

Yes, almost all of these software packages are customized by me. The startup script was not modified

I tried to proactively install nf_nathelper_extra, but failed

root@OpenWrt:/# insmod /etc/modules.d/
02-crypto-hash          09-crypto-sha512        mt7915e
04-crypto-crc32c        15-libphy               mt7996e
09-crypto-acompress     15-phylink              nf-conntrack
09-crypto-aead          18-phy-aquantia         nf-flow
09-crypto-authenc       20-usb-core             nf-log
09-crypto-ccm           30-gpio-button-hotplug  nf-nat
09-crypto-cmac          51-i2c-core             nf-nathelper
09-crypto-ctr           51-i2c-mux              nf-nathelper-extra
09-crypto-des           51-i2c-mux-pca954x      nf-reject
09-crypto-gcm           54-usb-xhci-hcd         nf-reject6
09-crypto-gf128         54-usb-xhci-mtk         nfnetlink
09-crypto-ghash         54-usb3                 nft-core
09-crypto-hmac          60-hwmon-pwmfan         nft-fib
09-crypto-manager       60-leds-gpio            nft-nat
09-crypto-md5           90-crypto-hw-safexcel   nft-offload
09-crypto-null          eeprom-at24             ppp
09-crypto-rng           lib-crc-ccitt           pppoe
09-crypto-seqiv         lib-crc32c              rtc-pcf8563
09-crypto-sha1          lib-lzo                 sfp
09-crypto-sha256        lib-textsearch
root@OpenWrt:/# insmod /etc/modules.d/nft-
nft-core     nft-fib      nft-nat      nft-offload
root@OpenWrt:/# insmod /etc/modules.d/nft-nat 
module is already loaded - nft-nat
root@OpenWrt:/# insmod /etc/modules.d/nft-
nft-core     nft-fib      nft-nat      nft-offload
root@OpenWrt:/# insmod /etc/modules.d/nf
nf-conntrack        nf-nathelper        nfnetlink           nft-offload
nf-flow             nf-nathelper-extra  nft-core
nf-log              nf-reject           nft-fib
nf-nat              nf-reject6          nft-nat
root@OpenWrt:/# insmod /etc/modules.d/nf-
nf-conntrack        nf-log              nf-nathelper        nf-reject
nf-flow             nf-nat              nf-nathelper-extra  nf-reject6
root@OpenWrt:/# insmod /etc/modules.d/nf-nat
nf-nat              nf-nathelper        nf-nathelper-extra
root@OpenWrt:/# insmod /etc/modules.d/nf-nathelper
nf-nathelper        nf-nathelper-extra
root@OpenWrt:/# insmod /etc/modules.d/nf-nathelper
failed to insert /etc/modules.d/nf-nathelper
root@OpenWrt:/# insmod /etc/modules.d/nf-nathelper-extra 
[  360.632555] Invalid ELF header magic: !=ELF
failed to insert /etc/modules.d/nf-nathelper-extra
root@OpenWrt:/# insmod /etc/modules.d/nf-nathelper-extra 
[  367.695653] Invalid ELF header magic: !=ELF
failed to insert /etc/modules.d/nf-nathelper-extra
root@OpenWrt:/# insmod /etc/modules.d/nf-nathelper
failed to insert /etc/modules.d/nf-nathelper
root@OpenWrt:/# 

It is so new I cannot even find a support thread for it.

But lots of questions about it.

You're right. I've decided to try again after a while. Thank you very much.

1 Like

Oh, here they are.