NAME
NetInfo - Defines machine interfaces to register with AFS servers
DESCRIPTION
There are two NetInfo files, one for an AFS client and one for an AFS
File Server or database server. The AFS client NetInfo file specifies
the IP addresses that the client should register with the File Servers
it connects to. The server NetInfo file specifies what interfaces
should be registered with AFS Database Servers or used to talk to other
database servers.
Client NetInfo
The client NetInfo file lists the IP addresses of one or more of the
local machine’s network interfaces. If it exists in the /etc/openafs
directory when the Cache Manager initializes, the Cache Manager uses
its contents as the basis for a list of local interfaces. Otherwise,
the Cache Manager uses the list of interfaces configured with the
operating system. It then removes from the list any addresses that
appear in the /etc/openafs/NetRestrict file, if it exists. The Cache
Manager records the resulting list in kernel memory. The first time it
establishes a connection to a File Server, it registers the list with
the File Server.
The File Server uses the addresses when it initiates a remote procedure
call (RPC) to the Cache Manager (as opposed to responding to an RPC
sent by the Cache Manager). There are two common circumstances in which
the File Server initiates RPCs: when it breaks callbacks and when it
pings the client machine to verify that the Cache Manager is still
accessible.
The NetInfo file is in ASCII format. One of the machine’s IP addresses
appears on each line, in dotted decimal format. The File Server
initially uses the address that appears first in the list. The order of
the remaining addresses is not significant: if an RPC to the first
interface fails, the File Server simultaneously sends RPCs to all of
the other interfaces in the list. Whichever interface replies first is
the one to which the File Server then sends pings and RPCs to break
callbacks.
To prohibit the Cache Manager absolutely from using one or more
addresses, list them in the NetRestrict file. To display the addresses
the Cache Manager is currently registering with File Servers, use the
fs getclientaddrs command. To replace the current list of interfaces
with a new one between reboots of the client machine, use the fs
setclientaddrs command.
Server NetInfo
The server NetInfo file, if present in the /var/lib/openafs/local
directory, defines the following:
· On a file server machine, the local interfaces that the File Server
(fileserver process) can register in the Volume Location Database
(VLDB) at initialization time.
· On a database server machine, the local interfaces that the Ubik
database synchronization library uses when communicating with the
database server processes running on other database server
machines.
If the NetInfo file exists when the File Server initializes, the File
Server uses its contents as the basis for a list of interfaces to
register in the VLDB. Otherwise, it uses the list of network interfaces
configured with the operating system. It then removes from the list any
addresses that appear in the /var/lib/openafs/local/NetRestrict file,
if it exists. The File Server records the resulting list in the
/var/lib/openafs/local/sysid file and registers the interfaces in the
VLDB. The database server processes use a similar procedure when
initializing, to determine which interfaces to use for communication
with the peer processes on other database machines in the cell.
The NetInfo file is in ASCII format. One of the machine’s IP addresses
appears on each line, in dotted decimal format. The order of the
addresses is not significant.
Optionally, the File Server can be forced to use an IP address that
does not belong to one of the server interfaces. To do this, add a line
to the NetInfo file with the IP address prefixed with "f" and a space.
This is useful when the File Server is on the interal side of a NAT
firewall.
To display the File Server interface addresses registered in the VLDB,
use the vos listaddrs command.
EXAMPLES
If the File Server is on the internal side of a NAT firewall, where it
serves internal clients using the IP address 192.168.1.123 and external
clients using the IP address 10.1.1.321, then the NetInfo file should
contain the following:
192.168.1.123
f 10.1.1.321
SEE ALSO
NetRestrict(5), sysid(5), vldb.DB0(5), fileserver(8),
fs_getclientaddrs(1), fs_setclientaddrs(1), vos_listaddrs(1)
COPYRIGHT
IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
This documentation is covered by the IBM Public License Version 1.0.
It was converted from HTML to POD by software written by Chas Williams
and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.