Installation guide

CTDB_NODES=/etc/ctdb/nodes
CTDB_PUBLIC_ADDRESSES=/etc/ctdb/public_addresses
CTDB_RECOVERY_LOCK="/mnt/ctdb/.ctdb.lock"
CTDB_MANAGES_SAMBA=yes
CTDB_MANAGES_WINBIND=yes
The meaning of these parameters is as follows.
C T D B_NO D ES
Specifies the location of the file which contains the cluster node list.
The /etc/ctd b/no d es file that C T D B_NO D ES references simply lists the IP addresses of
the cluster nodes, as in the following example:
192.168.1.151
192.168.1.152
192.168.1.153
In this example, there is only one interface/IP on each node that is used for both
cluster/CTDB communication and serving clients. However, it is highly recommended that
each cluster node have two network interfaces so that one set of interfaces can be
dedicated to cluster/CTDB communication and another set of interfaces can be dedicated
to public client access. Use the appropriate IP addresses of the cluster network here and
make sure the hostnames/IP addresses used in the cluster. co nf file are the same.
Similarly, use the appropriate interfaces of the public network for client access in the
publi c_add resses file.
It is critical that the /etc/ctd b/no d es file is identical on all nodes because the ordering is
important and CTDB will fail if it finds different information on different nodes.
C T D B_P UBLIC_AD D R ESSES
Specifies the location of the file that lists the IP addresses that can be used to access the
Samba shares exported by this cluster. These are the IP addresses that you should
configure in DNS for the name of the clustered Samba server and are the addresses that
CIFS clients will connect to. Configure the name of the clustered Samba server as one DNS
type A record with multiple IP addresses and let round-robin DNS distribute the clients
across the nodes of the cluster.
For this example, we have configured a round-robin DNS entry csmb-server with all the
addresses listed in the /etc/ctd b/publi c_ad d resses file. DNS will distribute the
clients that use this entry across the cluster in a round-robin fashion.
The contents of the /etc/ctdb/publi c_ad d resses file on each node are as follows:
192.168.1.201/0 eth0
192.168.1.202/0 eth0
192.168.1.203/0 eth0
This example uses three addresses that are currently unused on the network. In your own
configuration, choose addresses that can be accessed by the intended clients.
Alternately, this example shows the contents of the /etc/ctd b/publ i c_ad d resses files
in a cluster in which there are three nodes but a total of four public addresses. In this
example, IP address 198.162.2.1 can be hosted by either node 0 or node 1 and will be
available to clients as long as at least one of these nodes is available. Only if both nodes 0
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