Skip Navigation Links | |
Exit Print View | |
Sun QFS and Sun Storage Archive Manager 5.3 Reference Manual Sun QFS and Sun Storage Archive Manager 5.3 Information Library |
1. User Commands (Man Pages Section 1)
2. Maintenance Commands (Man Pages Section 1M)
3. Library Functions (Man Pages Section 3)
4. Library Functions (Man Pages Section 3X)
5. File Formats (Man Pages Section 4)
NAME hosts.fs.local - Local host information for Sun QFS shared file systems SYNOPSIS /etc/opt/SUNWsamfs/hosts.fs.local AVAILABILITY SUNWqfs SUNWsamfs DESCRIPTION A /etc/opt/SUNWsamfs/hosts.fs.local file can reside on each host system included in the Sun QFS shared file system. This file is used in conjuntion with the shared hosts file, which resides in the shared file system and is initialized by sammkfs(1M) from hosts.fs(4), to initialize network connections between the hosts of a shared file system. For more information, see the hosts.fs(4) and samsharefs(1M) man pages. The Sun QFS shared file system daemon uses the /etc/opt/SUNWsamfs/hosts.fs.local file and the shared hosts file present in the file system during initialization and reconfiguration to determine the server interfaces to which it should attempt to connect. Its function is to restrict the server interfaces to which each client connects. The fs portion of the name must be the family set name of the Sun QFS shared file system as specified in the mcf file. For more information on the mcf file, see the mcf(4) man page. Each line in the hosts.fs.local file corresponds to a possible metadata server. Each line contains the following fields: Field Number Content 1 The name of the host. This field contains the name of a potential metadata server host to which the local host can connect. This field must match the first field of the host in the shared hosts file. You can use the samsharefs(1M) command to verify the content of the fields of the shared hosts file. 2 A comma-separated list of host IP names or addresses. This should be a subset of the second field from the same hosts entry in the shared hosts file. The hosts.fs.local file is typically generated by copying the shared file system's shared hosts file to /etc/opt/SUNWsamfs/hosts.fs.local on each host. Each line referring to a non-server host is then deleted, and the third through fifth fields in the remaining lines are deleted. The network topology of the hosts is then examined in conjunction with the file, and the server interfaces that the local host should not attempt to connect to are removed from the second field. When all of these have been removed, the file is written out. The samd(1M) command is then used to cause any configuration changes to take effect. During startup and file system reconfiguration, the sam- sharefsd(1M) daemon attempts to connect to the server host. To do this, it searches the shared hosts file for the server's identity, and it extracts the list of IP names and addresses from the server's shared hosts file entry. The daemon then looks up the server's name in the file system's local hosts file, if any. If a local hosts file does not exist, the daemon uses the list from the shared hosts file. If the local hosts file does exist, then the corresponding list of host addresses is found in the local hosts file, the two lists of host addresses are searched (lexically) for common entries, and a common list is generated. The ordering of the list is determined by the local hosts file (left-most first). The names or addresses in the common list are looked up and used to attempt to connect to the server. If an attempt fails, the daemon attempts using any remaining addresses in order until all the addresses have been tried. EXAMPLES The following shared hosts configuration file supports a configuration in which two potential servers share a private interconnection and communicate to the other hosts sharing the file system using a separate network. The examples in this section show the hosts.shsam1.local files that can be found on the various hosts. # # shsam1 config, titan/tethys servers, mimas/dione clients # # This file goes in titan:/etc/opt/SUNWsamfs/hosts.shsam1, and # is used by 'mkfs -S shsam1' to initialize the FS meta data. # Subsequent changes to the configuration are made using # samsharefs(1M). # titan titan-ge,titan.xyzco.com 1 0 server tethys tethys-ge,tethys.xyzco.com 2 0 mimas mimas.xyzco.com 0 0 dione dione.xyzco.com 0 0 To ensure that titan and tethys always connect to each other through their private interfaces, titan-ge and tethys-ge, each requires a hosts.fs.local(4) file. To achieve this, files titan:/etc/opt/SUNWsamfs/hosts.shsam1.local and tethys:/etc/opt/SUNWsamfs/hosts.shsam1.local would contain the following lines: # # shsam1 server local config, titan/tethys servers, mimas/dione clients # titan titan-ge tethys tethys-ge To avoid the delays and inefficiencies of having mimas and dione attempt to connect to titan and tethys through the inaccessible, private titan-ge and tethys-ge interfaces, mimas and dione should also have their own hosts.fs.local(4) files. Files mimas:/etc/opt/SUNWsamfs/hosts.shsam1.local and dione:/etc/opt/SUNWsamfs/hosts.shsam1.local contain the following lines: # # shsam1 client local config, titan/tethys servers, mimas/dione clients # titan titan.xyzco.com tethys tethys.xyzco.com FILES /opt/SUNWsamfs/examples/hosts.shsam1 Contains an example of a hosts.fs file. /opt/SUNWsamfs/examples/hosts.shsam1.local.server /opt/SUNWsamfs/examples/hosts.shsam1.local.client Contain examples of hosts.fs.local files. SEE ALSO samfsck(1M), samfsconfig(1M), sammkfs(1M), samsharefs(1M), sam-sharefsd(1M). hosts.fs(4), mcf(4).