iptables and nf_conntrack

dafydd

Renowned Member
Apr 24, 2010
37
6
73
Cardiff, Wales
I updated a server to recent package versions but haven't yet rebooted into the kernel "4.13.8-3-pve" so its still on 4.13.4-1-pve

I see this warning in the system logs
"nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead."

And it looks like the FTP connection tracking into containers doesn't work any more (active FTP fails, passive is ok). The kernel modules are loaded:

nf_conntrack_ftp 20480 0
nf_conntrack 131072 4 nf_conntrack_ipv6,nf_conntrack_ftp,nf_conntrack_ipv4,xt_conntrack


Will this be fixed by a reboot? (I will have to schedule this out of hours)

root@bvmhost1:~# pveversion -v
proxmox-ve: 5.1-30 (running kernel: 4.13.4-1-pve)
pve-manager: 5.1-38 (running version: 5.1-38/1e9bc777)
pve-kernel-4.13.4-1-pve: 4.13.4-26
pve-kernel-4.10.17-4-pve: 4.10.17-24
pve-kernel-4.10.17-2-pve: 4.10.17-20
pve-kernel-4.13.8-3-pve: 4.13.8-30
pve-kernel-4.10.17-3-pve: 4.10.17-23
libpve-http-server-perl: 2.0-7
lvm2: 2.02.168-pve6
corosync: 2.4.2-pve3
libqb0: 1.0.1-1
pve-cluster: 5.0-19
qemu-server: 5.0-17
pve-firmware: 2.0-3
libpve-common-perl: 5.0-22
libpve-guest-common-perl: 2.0-13
libpve-access-control: 5.0-7
libpve-storage-perl: 5.0-17
pve-libspice-server1: 0.12.8-3
vncterm: 1.5-3
pve-docs: 5.1-12
pve-qemu-kvm: 2.9.1-3
pve-container: 2.0-17
pve-firewall: 3.0-5
pve-ha-manager: 2.0-4
ksm-control-daemon: 1.2-2
glusterfs-client: 3.8.8-1
lxc-pve: 2.1.1-2
lxcfs: 2.0.8-1
criu: 2.11.1-1~bpo90
novnc-pve: 0.6-4
smartmontools: 6.5+svn4324-1
zfsutils-linux: 0.7.3-pve1~bpo9
 
Ok a reboot didn't help, but I hadn't set sysctl.d with "net.netfilter.nf_conntrack_helper=1"
(I had done this on my other servers but for some reason had missed this particular one.
 

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