Topics: AIX, PowerHA / HACMP, System Admin

NFS mounts on HACMP failing

When you want to mount an NFS file system on a node of an HACMP cluster, there are a couple of items you need check, before it will work:

  • Make sure the hostname and IP address of the HACMP node are resolvable and provide the correct output, by running:
    # nslookup [hostname]
    # nslookup [ip-address]
  • The next thing you will want to check on the NFS server, if the node names of your HACMP cluster nodes are correctly added to the /etc/exports file. If they are, run:
    # exportfs -va
  • The last, and tricky item you will want to check is, if a service IP label is defined as an IP alias on the same adapter as your nodes hostname, e.g.:
    # netstat -nr
    Routing tables
    Destination   Gateway       Flags  Refs  Use    If  Exp  Groups
    Route Tree for Protocol Family 2 (Internet):
    default   UG      4    180100 en1  -     -  UHSb    0         0 en1  -     -     UGHS    3    791253 lo0  -     -
    The example above shows you that the default gateway is defined on the en1 interface. The next command shows you where your Service IP label lives:
    # netstat -i
    Name  Mtu   Network   Address         Ipkts   Ierrs Opkts
    en1   1500  link#2    0.2.55.d3.75.77 2587851 0      940024
    en1   1500  10.251.14 node01          2587851 0      940024
    en1   1500  10.251.20 serviceip       2587851 0      940024
    lo0   16896 link#1                    1912870 0     1914185
    lo0   16896 127       loopback        1912870 0     1914185
    lo0   16896 ::1                       1912870 0     1914185
    As you can see, the Service IP label (in the example above called "serviceip") is defined on en1. In that case, for NFS to work, you also want to add the "serviceip" to the /etc/exports file on the NFS server and re-run "exportfs -va". And you should also make sure that hostname "serviceip" resolves to an IP address correctly (and of course the IP address resolves to the correct hostname) on both the NFS server and the client.

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