Export NFS4 share and mount it using ipv6 address

Combining KVM and NFS4 I manage to have test/development environment on my laptop.Using KVM virtual machines images it is easy to clone them for various purposes.For software repository I use combination of ‘createrepo’ and repositories exported via NFS.
Recently I moved KVM test environment to ipv6 address space (will blog about procedure how to instruct KVM to start to use ipv6) and first thing I noticed is that nfs shares are not accessible any more on my quests systems as they were exported via ipv4 from host systems

# cat /etc/exports
/home/elvir/isoImages 192.168.122.0/24(rw,fsid=0,sync)

NFS4 supports ipv6, but we need to export nfs shares to ipv6 addresses.In my case,I decided to assign addresses from ipv6 address set 2000:aabb:ccdd:a::/64 and due to this added to /etc/exports below

/home/elvir/isoImages 2000:aabb:ccdd:a::/64(rw,fsid=0,sync)

with this I exported nfs shares to all hosts in ipv6 2000:aabb:ccdd:a::/64 network segment

ipv6 uses ip6tables,so it also necessary to edit /etc/sysconfig/ip6tables and open there access to port 2049/tcp ( nfs4 needs only this port to be open on server side )

We need ip6talbes rule as below

-A INPUT -m state --state NEW -m tcp -p tcp --dport 2049 -j ACCEPT

this is actually iptables syntax,but it only goes to ip6talbes file instead to iptables.
On RHEL/CentOS, you simply edit /etc/sysconfig/ip6tables and add there new rule

After this reload ip6tables rules,restart nfs,and re-export shares

# service ip6tables restart

  1. service nfs restart
  2. exportfs -av

On client side,mount command will be ( assuming nfs server has ipv6 address 2000:aabb:ccdd:a::1 )

# mount -t nfs4 '[2000:aabb:ccdd:a::1]':/ /home/nfs

Note that,in order to mount ipv6 nfs4 share,you will need to put ipv6 address between '[]'.Of course you can use hostnames instead of ipv6 addresses,but you will need to configure correct AAAA/PTR records in bind/dns configuration before dns names will work.

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#nfs4-ipv6-rhel6