Skip to main content

centos - Firewalld blocks IPv6, ignores config



I'm trying to setup an IPv6 web-server on CentOS 7.2 with NGINX. I have tested my IPv6 connectivity outgoing and incoming - everything works. My IP, AAAA records, etc as fine as well. Essentially everything is OK until I enable FirewallD.



I have it set up to default to the drop zone with eth0 interface. I have enabled dhcpv6-client, http, https and ssh (ssh is on a custom port). When the firewall is enabled no IPv6 traffic can leave or enter the machine. Traceroute6 to anything (even the gateway) only goes to localhost. If I disable the firewall, it's all good.



I have no idea why this is happening. I couldn't find anything online in order to make FirewallD apply the same IPv4 config to the IPv6 traffic. I personally thought, it would do that automatically, as all of its commands are IP protocol agnostic.



Any help is much appreciated.


Answer




I ran into the same issue. After following the logic through the rules that firewalld puts in I found that the drop zone was blocking ipv6 icmp that is needed to find the ipv6 neighbors. There is a rule to allow all ipv6 icmp but firewalld puts it after the input zones which is where the drop rules go.



If you want to see this for yourself just look at the output from 'ip6tables -L -n -v'



So, a quick and dirty fix is to do this:



firewall-cmd --permanent --direct --add-rule ipv6 filter INPUT 0 -p icmpv6 -j ACCEPT


Firewalld puts the direct rules before the other input rules so that will happen before the drop rules. If you want to block things like ping you would also use a direct rule but you would need it before the rule above.




You would do something like:



firewall-cmd --permanent --direct --add-rule ipv6 filter INPUT 0 -p icmpv6 --icmpv6-type 128 -j DROP
firewall-cmd --permanent --direct --add-rule ipv6 filter INPUT 1 -p icmpv6 -j ACCEPT


The priorities will keep them in order.


Comments

Popular posts from this blog

linux - Awstats - outputting stats for merged Access_logs only producing stats for one server's log

I've been attempting this for two weeks and I've accessed countless number of sites on this issue and it seems there is something I'm not getting here and I'm at a lost. I manged to figure out how to merge logs from two servers together. (Taking care to only merge the matching domains together) The logs from the first server span from 15 Dec 2012 to 8 April 2014 The logs from the second server span from 2 Mar 2014 to 9 April 2014 I was able to successfully merge them using the logresolvemerge.pl script simply enermerating each log and > out_putting_it_to_file Looking at the two logs from each server the format seems exactly the same. The problem I'm having is producing the stats page for the logs. The command I've boiled it down to is /usr/share/awstats/tools/awstats_buildstaticpages.pl -configdir=/home/User/Documents/conf/ -config=example.com awstatsprog=/usr/share/awstats/wwwroot/cgi-bin/awstats.pl dir=/home/User/Documents/parced -month=all -year=all...

iLO 3 Firmware Update (HP Proliant DL380 G7)

The iLO web interface allows me to upload a .bin file ( Obtain the firmware image (.bin) file from the Online ROM Flash Component for HP Integrated Lights-Out. ) The iLO web interface redirects me to a page in the HP support website ( http://www.hp.com/go/iLO ) where I am supposed to find this .bin firmware, but no luck for me. The support website is a mess and very slow, badly categorized and generally unusable. Where can I find this .bin file? The only related link I am able to find asks me about my server operating system (what does this have to do with the iLO?!) and lets me download an .iso with no .bin file And also a related question: what is the latest iLO 3 version? (for Proliant DL380 G7, not sure if the iLO is tied to the server model)

hp proliant - Smart Array P822 with HBA Mode?

We get an HP DL360 G8 with an Smart Array P822 controller. On that controller will come a HP StorageWorks D2700 . Does anybody know, that it is possible to run the Smart Array P822 in HBA mode? I found only information about the P410i, who can run HBA. If this is not supported, what you think about the LSI 9207-8e controller? Will this fit good in that setup? The Hardware we get is used but all original from HP. The StorageWorks has 25 x 900 GB SAS 10K disks. Because the disks are not new I would like to use only 22 for raid6, and the rest for spare (I need to see if the disk count is optimal or not for zfs). It would be nice if I'm not stick to SAS in future. As OS I would like to install debian stretch with zfs 0.71 as file system and software raid. I have see that hp has an page for debian to. I would like to use hba mode because it is recommend, that zfs know at most as possible about the disk, and I'm independent from the raid controller. For us zfs have many benefits, ...