LIST OF KNOWN BUGS IN AM-UTILS OR OPERATING SYSTEMS Note: report am-utils bugs via Bugzilla to https://bugzilla.am-utils.org/ or by email to the am-utils mailing list (see www.am-utils.org). (1) mips-sgi-irix* [1A] known to have flaky NFS V.3 and TCP. Amd tends to hang or spin infinitely after a few hours or days of use. Users must install recommended patches from vendor. Patches help, but not all the time. Otherwise avoid using NFS V.3 and TCP on these systems, by setting /defaults opts:=vers=2,proto=udp [1B] yp_all() leaks a file descriptor. Eventually amd runs out of file descriptors and hangs. Am-utils circumvents this by using its own version of yp_all which uses udp and iterates over NIS maps. The latter isn't as reliable as yp_all() which uses TCP, but it is better than hanging. (I have some reports that older version of hpux-9, with older libc, also leak file descriptors.) [1C] SGI's MIPSpro C compiler on IRIX 6 has the unfortunate habit of creating code specificially for the machine it runs on. The ABI and ISA used depend very much on the OS version and compiler release used. This means that the resulting amd binary won't run on machines different from the build host, particularly older ones. Older versions of am-utils enforced the O32 ABI when compiling with cc to work around this, but this ABI is deprecated in favor of the N32 ABI now, so we use -n32 -mips3 to ensure that the binaries run on every host capable of running IRIX 6 at all. If this is not appropriate for you, configure with something like CC='cc -64' instead to get the desired ABI and ISA. (2) alpha-unknown-linux-gnu (RedHat Linux 4.2) hasmntopt(mnt, opt) can go into an infinite loop if opt is any substring of mnt->mnt_opts. Redhat 5.0 does not have this libc bug. Here is an example program: #include #include main() { struct mntent mnt; char *cp; mnt.mnt_opts = "intr,rw,port=1023,timeo=8,foo=br,retrans=110,indirect,map=/usr/local/AMD/etc/amd.proj,boo"; cp = hasmntopt(&mnt, "ro"); printf("cp = %s\n", cp); exit(0); } It is possible that sufficiently newer version of libc for RH4.2 fix this problem. (3) mips-dec-ultrix4.3 Rainer Orth reports [3A] One needs the Kernel Config Files (UDTBIN430) subset installed to compile am-utils, otherwise essential header files (net/if.h, net/route.h, rpcsvc/mount.h, rpcsvc/yp_prot.h, rpcsvc/ypclnt.h, sys/proc.h) are missing. [3B] It's probably impossible to build am-utils with DEC C on Ultrix V4.3. This compiler is pseudo-ANSI only. Maybe the new ANSI C compiler in V4.3A and beyond will do. I successfully used gcc 2.8.1. [3C] You need to build against a recent libhesiod (I used 3.0.2) and libresolv/lib44bsd (I used BIND 4.9.5-P1). The resolver routines in libc seem to cause random memory corruption. It is necessary to specify LIBS=-l44bsd. lib44bsd is a helper library of libresolv used to supply functions like strdup which are missing on the host system. This isn't currently autoconfiscated. [3D] You need to configure with CONFIG_SHELL=/bin/sh5 /bin/sh5 buildall; /bin/sh cannot handle the shell functions used in buildall and is both buggy and slow. [3E] At least the gcc 2.7.0 fixincludes-mangled needs a forward declaration of struct utsname to avoid lots of gcc warnings: RCS file: RCS/utsname.h,v retrieving revision 1.1 diff -u -r1.1 utsname.h --- utsname.h 1995/06/19 13:07:01 1.1 +++ utsname.h 1998/01/27 12:34:26 @@ -59,6 +59,7 @@ #ifdef KERNEL #include "../h/limits.h" #else /* user mode */ +struct utsname; extern int uname _PARAMS((struct utsname *)); #endif #define __SYS_NMLN 32 (4) powerpc-ibm-aix4.2.1.0 [4A] "Randall S. Winchester" reports that for amd to start, you need to kill and restart rpc.mountd and possibly also make sure that nfsd is running. Normally these are not required. [4B] "Stefan Vogel" reports that if your amq executable dump core unexpectedly, then it may be a bug in gcc 2.7.x. Upgrade to gcc 2.8.x or use IBM's xlC compiler. [C] Do not link amd with libnsl. It is buggy and causes amd to core dump in strlen inside strdup inside svc_register(). (5) *-linux-rh51 (RedHat Linux 5.1) There's a UDP file descriptor leak in libnsl in RedHat Linux 5.1. This library part of glibc2. Am-utils currently declares redhat 5.1 systems as having a "broken yp_all" and using an internal, slower, leak-free version. The leak is known to the glibc maintainers and a fix from them is due soon, but it is not yet in the glibc-2.0.7-19 RPM. (6) rs6000-ibm-aix4.1.x A bug in libc results in an amq binary that doesn't work; amq -v dumps core in xdr_string. There is no known fix (source code or vendor patch) at this time. (Please let us know if you have a fix; see www.am-utils.org.) (7) *-aix4.3.2.0 The plock() function will pre-reserve all of the memory up to the maximum listed in the ulimit. If the ulimit is infinite, plock() will try to take all of the system's memory, and fail with ENOMEM (Not Enough Space). Normally ulimit may be set to a few gigs of max memory usage, but even that is too much; Amd doesn't need more than a few megs of resident memory size (depending on the particular usage, number of maps, etc.) Solution: lower your ulimit before starting amd. This can be done inside the ctl-amd script, but be careful not to limit it too low. Alternatively, don't use plock on aix-4.3: set it to plock=no in amd.conf (which is the default if you do nothing). (8) *-linux (systems using glibc 2.1, such as RedHat-6.x) There's a UDP file descriptor leak in the NIS routines in glibc, especially those that do yp_bind. Until this is bug fixed, do not set nis_domain in amd.conf, but let the system pick up the default domain name as set by your system. That would avoid using the buggy yp_bind routines in libc. (9) *-linux (SuSE systems using unfsd) The user-level nfsd (2.2beta44) on older SuSE Linux systems (and possibly others) dies with a SEGV when amd tries to contact it for access to a volume that does not exist, or one for which there is no permission to mount. (10) *-*-hpux11 If you're using NFSv3, you must install HP patches PHNE_20344 and PHNE_20371. If you don't, and you try to use amd with NFSv3 over TCP, your kernel will panic. (11) *-linux* (any system using a 2.2.18+ kernel) The Linux kernels don't support Amd's direct mounts very well, leading to erratic behavior: shares that don't get remounted after the first timeout, inability to restart Amd because its mount points cannot be unmounted, etc. There are some kernel patches on the am-utils Web site, which solve these problems. See http://www.am-utils.org/patches/. Later 2.4.x kernels completely disallow the hack amd was using for direct mounts, so another solution will have to be found. Note: the above is for the old-style amd mount_type = nfs. The autofs mounts don't support direct mounts at all (due to lack of kernel support). (12) *-aix5.1.0.0 and *-hpux9* /bin/sh is broken and fails to run the configure script properly. You need to use /bin/ksh instead. The buildall script will do it for you; if for some reason you need to run configure directly, run it using 'ksh configure' instead of just 'configure'. [12A] *-aix5.2.* Apparently there is an NFS client side bug in vmount() which causes amd to hang when it starts (and tries to NFS-mount itself). According to IBM engineers, this has to do with partial support code for IPv6: the NFS kernel code doesn't appear to recognize the sin_family of the amd vmount(), although amd does the right thing. The bug doesn't appear to be in 5.1 or 4.3.3. A fix from IBM is available, APAR number IY41417. A binary built on 4.3.3 will not work on 5.2, because the kernel ABIs have changed. [12C] *-aix* It is important that you install bos.net.nfs.adt before configuring and building am-utils. If you don't, you will get compile-time or configure-time errors, especially when configure tries to find AIX's definition of struct nfs_args. (13) *-linux and *-darwin6.0 Certain linux kernels (2.4.18+ are fine, 2.4.10- are probably bad, those in between have not been tested) have a bug which causes them to reconnect broken NFS/TCP connections using unprivileged ports (greater than 1024), unlike the initial connections which do originate from privileged ports. This can upset quite a few NFS servers and causes accesses to the mounted shares to fail with "Operation not permitted" (EPERM). The darwin (MacOS X) kernel defaults to using unprivileged ports, but that can be changed by setting the resvport mount flag (which amd sets by default). Nonetheless, if a TCP connection breaks, under certain unclear circumstances the kernel might "forget" about that flag and start using unprivileged ports, causing the same EPERM error above. (14) Solaris The line "%option" in *.l files may cause Solaris /usr/ccs/bin/lex to abort with the error "missing translation value." This is a bug in Solaris lex. Moreover, both Solaris yacc and lex produce code that does not pass strict compilation such as "gcc -Wall -Werror". Use GNU Flex and Bison instead. You can download ready-made binaries from www.sunfreeware.com. Note, however, that sometimes the binaries on sunfreeware.com don't seem to work, often because they are built against an older revision of Solaris or build tools. In that case, build a fresh version of GNU flex and/or bison from the latest stable sources. See http://www.gnu.org/software/flex/ and http://www.gnu.org/software/bison/. (15) Solaris 8 + patch 10899[34]-xx (18 <= xx < 25) or patch 11260[56]-xx With this patch, Sun updated the autofs kernel module and automountd userspace daemon from version 3 to version 4. They also updated the /usr/include/rpcsvc/autofs_prot.x file, but forgot to regenerate the autofs_prot.h file. Thus, when amd is compiled, it uses the old header and thinks it should use autofs version 3, when in fact the kernel now supports (and expects) only version 4. The workaround is to run 'rpcgen -C -h /usr/include/rpcsvc/autofs_prot.x > /usr/include/rpcsvc/autofs_prot.h' and completely reconfigure and rebuild am-utils (removing config.cache before running configure). The problem is fixed in patch revisions 10899[34]-25 and up. (16) Linux kernel 2.4+ and lofs mounts Lofs mounts are not supported by the linux kernel, at all, but since 2.4.0 the kernel supports a similar type of mount called a bind mount. Its semantics are closer to those of a hardlink than to those of lofs, and one of the results is that bind mounts ignore any mount options paseed to them. Amd uses bind mounts internally to emulate lofs mounts, which means that lofs mounts on linux will effectively ignore their mount parameters and inherit whatever options the original filesystem mounted upon had. (17) autoconf 2.57 If you see configure warnings of the following kind: configure: WARNING: sys/proc.h: present but cannot be compiled configure: WARNING: sys/proc.h: check for missing prerequisite headers? configure: WARNING: sys/proc.h: proceeding with the preprocessor's result configure: WARNING: ## ------------------------------------ ## configure: WARNING: ## Report this to bug-autoconf@gnu.org. ## configure: WARNING: ## ------------------------------------ ## please ignore them. They are not real errors, and neither bug-autoconf@gnu.org nor the am-utils maintainers are interested in hearing about them. Autoconf simply tries to do more than we need and attempts to compile each header in isolation, which fails for many system headers. That's ok, because we only need to know if a header file exists -- we know how to use it properly ourselves. While autoconf does offer a way to specify other files to be included with the tested header, in order to avoid these warnings, using it would enlarge the resulting configure script by an order of magnitude, and for no real gain. Configure is big enough as it is, we don't need any more useless baggage in it. (18) NetBSD 2.0.2, FreeBSD 5.4, OpenBSD 3.7, and quite possibly most other BSDs and other OSs (as of September 2005) Some BSD kernels don't have a way to turn off the NFS attribute cache. They don't have a 'noac' mount flag, and setting various cache timeout fields in struct nfs_args doesn't turn off the attribute cache; instead, it sets the attribute cache timeout to some internal hard-coded default (usually anywhere from 5-30 seconds). If Amd cannot turn off the NFS attribute cache, under heavy Amd usage, users could get ESTALE errors from automounted symlinks, or find that those symlinks point to the wrong place. One workaround which would minimize this effect is to set auto_attrcache=1 in your amd.conf, but it doesn't eliminate the problem! The best solutions are (1) to use Amd in Autofs mode, if it's supported in your OS, and (2) talk to your OS vendor to support a true "noac" flag. See README.attrcache for more details. Erez & the am-utils team.