Re: FreeBSD pkg HOST-RESOURCES-MIB::hrSWInstalled stops working

On Mon, May 7, 2018, at 15:08, Robert Story wrote:
> On Mon, 07 May 2018 11:44:59 -0500 Mark wrote:
> MF> The HOST-RESOURCES-MIB::hrSWInstalled support for FreeBSD pkg
> MF> stops working after so many queries and requires an snmpd
> MF> process restart. I have been observing this for quite some time
> MF> and have only recently started to debug it. The code in
> MF> question is at:
> MF> 
> MF> agent/mibgroup/host/data_access/swinst_pkginfo.c
> MF> 
> MF> When debugging I see it throw either:
> MF> 
> MF> snmp_log( LOG_ERR, "SWInst: error initializing pkgng db\n" );
> MF> 
> MF> or
> MF> 
> MF> snmp_log( LOG_ERR, "SWInst: error opening pkgng db\n" );
> MF> 
> MF> neither of which should be true as nothing on the system
> MF> changes. After seeing one of these for a few times there are no
> MF> further messages [...]
> 
> Can you run with "-Dswinst:load:arch --logTimestamp=yes", and
> then run "grep -i swinst" on the log file and send it?
> 
> MF> Could anyone provide any possible insight or ideas on what
> MF> could be the issue here? I have compared the code with that
> MF> used internally in FreeBSD pkg tool and it's nearly identical.
> MF> The only thing that I felt was missing was declaring a readonly
> MF> lock on the database but even adding that into the snmp code
> MF> had no effect...
> 
> There are quite a few places that don't clean up properly before
> returning, but that should only affect error paths.
> 
> You can also try this patch to see if you get more useful debug
> info:
> 
> diff --git a/agent/mibgroup/host/data_access/swinst_pkginfo.c b/agent/
> mibgroup/host/data_access/swinst_pkginfo.c
> index 861d79f0f..de2abf19b 100644
> --- a/agent/mibgroup/host/data_access/swinst_pkginfo.c
> +++ b/agent/mibgroup/host/data_access/swinst_pkginfo.c
> @@ -118,12 +118,15 @@ netsnmp_swinst_arch_load( netsnmp_container 
> *container, u_int flags)
> 
>      if (pkgdb_open(&db, PKGDB_DEFAULT) != EPKG_OK) {
>         snmp_log( LOG_ERR, "SWInst: error opening pkgng db\n" );
> +        pkg_shutdown();
>         return 1;
>      }
> 
>      if (pkg_status(NULL) == PKG_STATUS_ACTIVE) {
>         pkgng = 1;
>      } else {
> +        pkgdb_close(db);
> +        pkg_shutdown();
>         snmp_log( LOG_INFO, "SWInst: not a pkgng system\n" );
>      }
> 
> @@ -131,9 +134,12 @@ netsnmp_swinst_arch_load( netsnmp_container 
> *container, u_int flags)
>      if (pkgng) {
>          if ((it = pkgdb_query(db, NULL, MATCH_ALL)) == NULL) {
>              snmp_log( LOG_ERR, "SWInst: error querying pkgng db\n" );
> +            pkgdb_close(db);
> +            pkg_shutdown();
>              return 1;
>          }
> 
> +        DEBUGMSGTL(("swinst:load:arch"," pkgdb available\n"));
>          while (pkgdb_it_next(it, &pkg, PKG_LOAD_BASIC) == EPKG_OK) {
>              pkg_snprintf(pkgname, sizeof(pkgname), "%n-%v", pkg, pkg);
>              pkg_snprintf(pkgdate, sizeof(pkgdate), "%t", pkg);
> @@ -162,13 +168,18 @@ netsnmp_swinst_arch_load( netsnmp_container 
> *container, u_int flags)
>      } else {
>  #endif /* HAVE_LIBPKG */
>          if ( !pkg_directory[0] ) {
> +            NETSNMP_LOGONCE(LOG_ERR, "SWInst: no pkg_directory 
> available\n");
>              return 1;    /* Can't report installed packages
>                           if there isn't a list of them! */
>          }
> 
> +        DEBUGMSGTL(("swinst:load:arch"," pkgdb available\n"));
>          d = opendir( pkg_directory );
> -        if (!d)
> +        if (!d) {
> +            snmp_log( LOG_ERR, "SWInst: error querying pkg_directory %s\n",
> +                      pkg_directory );
>              return 1;
> +        }
> 
>          while ((dp = readdir(d)) != NULL) {
>              if ( '.' == dp->d_name[0] )


Hi Robert,

I had to tweak your patch slightly, but this is the result showing it working and then suddenly it stops.


2018-05-11 17:11:42     -- hrSWInstalledDate.241
2018-05-11 17:11:42     -- hrSWInstalledDate.242
2018-05-11 17:11:42     -- hrSWInstalledDate.243
2018-05-11 17:11:42     -- hrSWInstalledDate.244
2018-05-11 17:11:42     -- hrSWInstalledDate.245
2018-05-11 17:11:42     -- hrSWInstalledDate.246
2018-05-11 17:11:42     -- hrSWInstalledDate.247
2018-05-11 17:11:42     -- hrSWInstalledDate.248
2018-05-11 17:11:43     -- hrSWInstalled
2018-05-11 17:11:43 SWInst: error opening pkgng db
2018-05-11 17:11:43     -- hrSWInstalled
2018-05-11 17:11:50     -- hrSWInstalled
2018-05-11 17:11:50     -- hrSWInstalled
2018-05-11 17:11:58     -- hrSWInstalled
2018-05-11 17:11:58     -- hrSWInstalled
2018-05-11 17:12:02     -- hrSWInstalled
2018-05-11 17:12:02     -- hrSWInstalled


Patch change was  NETSNMP_LOGONCE() -> snmp_log() because it didn't like it:

host/data_access/swinst_pkginfo.c:170:38: error: too many arguments provided to function-like macro invocation
            NETSNMP_LOGONCE(LOG_ERR, "SWInst: no pkg_directory available\n");


Thanks for your time.


Mark


-- 
  Mark Felder
  ports-secteam & portmgr member
  [email protected]

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