Data Doman – manipulate interface used for replication

When we deployed our second Data Domain i wanted to start migrating some shares from the old DD880 to the new DD890.  We have multiple virtual interfaces on DD880 and DD890  and i wanted to make sure that replication traffic was using specific interfaces that had layer 2 connectivity. I have documented the steps how to manipulate replication interfaces.

Configuration:

Source – DD880 – OS 5.1.1.0-291218

DNS Name – DD880PROD  – virtual interface name used for host backups
DNS Name – DD880PRIV – virtual interface i want to use for replication

DD880PROD# net show settings 
port         enabled   DHCP   IP address       netmask           type   additional setting   
----------   -------   ----   --------------   ---------------   ----   ---------------------
eth0a        yes       no     10.12.24.51      255.255.255.0     n/a                         
eth0b        yes       no     192.168.1.3      255.255.255.0     n/a                         
eth5a        yes       n/a    n/a              n/a               n/a    bonded to veth0      
eth5b        yes       n/a    n/a              n/a               n/a    bonded to veth0      
veth0        yes       no     0                255.255.252.0     n/a    failover: eth5a,eth5b
veth0.2694   yes       no     128.140.38.136   255.255.255.128   n/a    << --- Production (DNS Name DD880PROD)           
veth0.3442   yes       no     10.140.32.25     255.255.255.128   n/a    << -- Private      (DNS Name DD880PRIV)

Target – DD890 – OS 5.1.1.0-291218

DNS Name – DD890PROD  – virtual interface name used for host backups
DNS Name – DD890PRIV – virtual interface i want to use for replication

DD890PROD# net show settings
port         enabled   DHCP   IP address       netmask         type   additional setting             
----------   -------   ----   --------------   -------------   ----   -------------------------------
eth0a        no        n/a    n/a              n/a             n/a                                   
eth0b        no        n/a    n/a              n/a             n/a                                   
eth4a        yes       n/a    n/a              n/a             n/a    bonded to veth0                
eth4b        yes       n/a    n/a              n/a             n/a    bonded to veth0                
veth0        yes       no     0                255.255.255.0   n/a    lacp hash xor-L3L4: eth4a,eth4b
veth0.2997   yes       no     128.199.145.250  255.255.255.0   n/a    << --- Production (DNS Name DD890PROD)                            
veth0.3442   yes       no     10.140.32.26     255.255.255.128 n/a    << -- Private      (DNS Name DD890PRIV)

When you configure Data Domain replication session you have to specify host name assigned to Data Domain, you can get it by typing “hostname” and the prompt (it is case sensitive).

  • Let’s go ahead and create the session first, run this command on both source and target DD
replication add source dir://DD880PROD.mycompany.local/backup/oracle destination dir://DD890PROD.mycompany.local/backup/oracle
  • Verify session got created, also notice Connection Host. This is my production interface that i do not want to use for replication.
DD880PROD# replication show config
CTX   Source                                                       Destination                      Connection Host and Port                Low-bw-optim   Enabled

---   -------------------------------------------    ---------------------------------------------  -------------------------------------   ------------   -------

1    dir://DD880PROD.mycompany.local/backup/oracle   dir://DD890PROD.mycompany.local/backup/oracle  DD880PROD.mycompany.local   (default)     disabled       yes
  • Now let’s modify this session on each Data Domain so it uses private interfaces

On source (DD880)

replication modify rctx://1 connection-host DD890PRIV.mycompany.local

On target (DD890)

replication modify rctx://1 connection-host DD880PRIV.mycompany.local
  • Let’s see what it looks like (on source), notice it’s now displaying correct Connection Host name
DD880PROD# replication show config
CTX   Source                                                       Destination                      Connection Host and Port                Low-bw-optim   Enabled

---   -------------------------------------------    ---------------------------------------------  -------------------------------------   ------------   -------

1    dir://DD880PROD.mycompany.local/backup/oracle   dir://DD890PROD.mycompany.local/backup/oracle  DD880PRIV.mycompany.local   (default)     disabled       yes
  • At this point we are ready to start replication session, if you have issues starting the session make sure you don’t need to add any static routes
replication initialize dir://DD890PROD.mycompany.local/backup/oracle