register ourselves as an NIS version 1 UDP server to pacify older SunOS 4
ypbinds that seem to insist on having one around. All this does is allow
ypserv to respond to DOMAIN_NONACK requests that are periodically
transmitted by ypbind: the server will not actually work as an NIS v1
server in any other way.
Unlike the mainline code, which implements this as a compile-time
option, this feature can be turned on with the newly-added -k flag
at runtime.
Bunped version number to 0.13. (What the hell.)
Updated the man page to reflect this change, also made a couple of small
edits to reflect the recent changes in the /etc/rc* setup.
select() returns EINVAL if you try to feed it a value of FD_SETSIZE greater
that 256. You can apparently adjust this by specifying a larger value of
FD_SETSIZE when configuring your kernel. However, if you set the maximum
number of open file descriptors per process to some value greater than
the FD_SETSIZE value that select() expects, many selects() within the RPC
library code will be botched because _rpc_dtablesize() will return
invalid numbers. This is to say that it will return the upper descriptor
table size limit which can be much higher than 256. Unless select() is
prepared to expect this 'unusually' high value, it will fail. (A good
example of this can be seen with NIS enabled: if you type 'unlimit' at
the shell prompt and then run any command that does NIS calls, you'll
be bombarded with errors from clnttcp_create().)
A temporary fix for this is to clamp the value returned by _rpc_dtablesize()
at FD_SETSIZE (as defined in <sys/types.h> (256)). I suppose the Right
Thing would be to provide some mechanism for select() to dynamically
adjust itself to handle FD_SETSIZE values larger than 256, but it's a
bit late in the game for that. Hopefully 256 file descriptors will be enough
to keep RPC happy for now.
add #includes for YP headers when compiling with -DYP to avoid some implicit
declarations.
getgrent.c & getnetgrent.c: add some #includes to avoid implicit declarations
of YP functions.
Added a new type to uiomove - "UIO_NOCOPY" which causes it to update
pointers and counts, but doesn't do any data copying. This is needed
for upcoming changes to the way that the vnode pager does its page
outs.
Added a new hash init function call "phashinit" that allocates and
initializes a prime number sized hash table.
vfs_cache.c:
Changed hashing algorithm to use the remainder of dividing by a prime
number to improve the distribution characteristcs. Uses new phashinit
function in kern_subr.c.
will cause kernel compiles to work even if the src/includes directory
doesn't exist but still do the 'Right Thing' and pull files from the
source tree if it does exist.
Reviewed by: Bruce Evans
Obtained from: Casper H. Dik (by vay of Usenet)
Small patch to help improve NIS rebinding times (among other things):
>From: casper@fwi.uva.nl (Casper H.S. Dik)
>Newsgroups: comp.sys.sun.misc,comp.sys.sun.admin
>Subject: FIX for slow rebinding of NIS.
>Summary: a small change in libc makes life with NIS a lot easier.
>Message-ID: <1992Jan17.173905.11727@fwi.uva.nl>
>Date: 17 Jan 92 17:39:05 GMT
>Sender: news@fwi.uva.nl
>Organization: FWI, University of Amsterdam
>Lines: 138
>Nntp-Posting-Host: halo.fwi.uva.nl
Have you been plagued by long waits when your NIS server is rebooted?
READ ON!
Sun has a patch, but the README says:
********************* WARNING ******************************
This is a new version of ypbind that never uses the NIS
binding file to cache the servers binding. This will have
the effect of fixing the current symptom. However, it might
degrade the overall performance of the system when the
server is available. This is most likely to happen on an
overloaded server, which will cause the network to produce
a broadcast storm.
*************************************************************
Therefor, I have produced another fix.
o What goes wrong.
When the NIS server is rebooted, ypserv will obtain different ports
to listen for RPC requests. All clients will continue to use the old
binding they obtained earlier. The NIS server will send ICMP dst unreachable
messages for the RPC requests that arrive at the old port. These ICMPs
are dropped on the floor and the client code will continue sending the
requests until the timer has expired. The small fix at the end of this
message will pick up these ICMP messages and deliver them to the RPC layer.
o Before and after.
I've tested this on some machines and this is the result:
(kill and restart ypserv on the server)
original% time ypmatch user passwd
user:....
0.040u 0.090s 2:35.64 0.0% 0+126k 0+0io 0pf+0w (155 seconds elapsed time)
fixedhost% time ypmatch user passwd
user:....
0.050u 0.050s 0:10.20 0.9% 0+136k 0+0io 0pf+0w (10 seconds elapsed time)
Rebinding is almost instantaneous.
o Other benefits.
RPC calls that use UDP as transport will no longer time out but
will abort much sooner. (E.g., the remote host is unreachable or
111/udp is filtered by an intermediate router)
ypxfr can't easily be reduced down to one file like yppush because it
needs to do certain special things (such as binding to a specific
machine (the NIS master)) which the yp_*() functions in libc don't
allow.
to open the mounted block device containing the directory to put the bad
sector files in, and opening of mounted block devices hasn't been allowed
since Net/2 or before. Attempt to open the raw device instead. Be more
careful about long names.
Use lstat() instead of stat() to search for block devices so that my
symlink to the default floppy doesn't cause problems.
Check for truncation of the block number when it is squeezed through the
mknod() interface. The maximum used to be only 32767, but now it large
enough.
#179). The fix implements a ttyhalfclose() (sort of), resetting the
session and pgrp pointers when the physical device is about to be
closed.
Suggested by: bde
old type (stty) ioctls can easily bypass locking bits.
It involves manual conversion from old ioctls to new ones,
large piece of code duplicated from tty_compat.c
ypbind is supposed to create it but it doesn't. This is because when
it checks the return value for the attempted open() of
/var/yp/binding/DOMAIN.VERSION, it tests only for a value of -1. This
is bogus because open() doesn't return -1 in this case. Now it checks
for < 0 instead.
This should make life easier for many NIS-newbies who would otherwise
be left scratching their heads wondering why the NIS client stuff won't
work despite their best efforts. ("I set the domain name on my machine,
and /var/yp exists, but when I start ypbind and try a 'ypcat passwd,'
it says it can't bind to a server for this domain! Please help!")
*long, heavy sigh*
