Editing Net-SNMP subagent

Here is snmp subagent to export UBC via SNMP protocol.

Author - n1ckname


=== /etc/snmp/snmpagent.pl ===

  #!/usr/bin/perl 
  
  $program = $0;
  
  use NetSNMP::OID (':all');
  use NetSNMP::agent (':all');
  use NetSNMP::ASN (':all');
  use Data::Dumper;
  my $debug = 0;
  my @resName=qw(name vmguarpages tcpsndbuf othersockbuf physpages numfile numtcpsock numpty numsiginfo tcprcvbuf dcachesize numiptent numothersock privvmpages kmemsize numflock shmpages lockedpages dummy numproc oomguarpages dgramrcvbuf);
  my @catName=qw(held maxheld barrier limit failcnt);
  my %resIndex,%catIndex;
  @resIndex{@resName} = (0..$#resName);
  @catIndex{@catName} = (0..$#catName);
  
  sub handler { 
      my ($handler, $reg_info, $request_info, $requests) = @_; 
      open(UB,"<$source");
      while(<UB>){
          my %vmachine;
          if ( /\D*(\d+):[\s\t]+([a-z]+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+).*/ ){ 
  	    $vid=$1; 
  	    $beancounters{$vid}=\%vmachine ; 
              ${beancounters{$vid}{0}}="www";
  	    open(CONF,"</etc/vz/conf/$vid.conf");
  	    my $name=$vid;
  	    while(<CONF>) {
  		if(/NAME[\s\t]?=[\s\t]?["]?([^"]+)["]?/)  {
  		    $name=$1;
  		    last;
  		    #"
  		}
  	    }
  	    ${beancounters{$vid}{0}}=$name;
              $resource=$2 ;
              $held=$3 ;
              $maxheld=$4 ;
              $barrier=$5 ;
              $limit=$6 ;
              $failcnt=$7 ;
              ${beancounters{$vid}}{${resIndex{$resource}}}=[$held , $maxheld , $barrier , $limit ,$failcnt ];
  
  	}
          if ( /^[\W\d]+([a-z]+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+)[\t\s]+(\d+).*/ ) {
                  $resource=$1 ;
                  $held=$2 ;
                  $maxheld=$3 ;
                  $barrier=$4 ;
                  $limit=$5 ;
                  $failcnt=$6 ;
                  ${beancounters{$vid}}{${resIndex{$resource}}}=[$held , $maxheld , $barrier , $limit ,$failcnt ];
          }
      }
      close(UB);
  
      for ( my $request = $requests; $request; $request = $request->next() ) {
      
          my $reqOID = $request->getOID();
          my $reqMode = $request_info->getMode();
  	my $myOID = new NetSNMP::OID($OID);
  #1.3.6.1.4.1.2021.51.ctcount = 5
  #1.3.6.1.4.1.2021.51.ct.101.name = www
  #1.3.6.1.4.1.2021.51.ct.101.kmemsize.held = 458584
  #1.3.6.1.4.1.2021.51.ct.101.kmemsize.maxheld = 1490364
  #1.3.6.1.4.1.2021.51.ct.101.kmemsize.barrier = 11055923
  
  #		$request->setValue(ASN_INTEGER, scalar keys (%beancounters));
  
          if ($reqMode == MODE_GET) {
  	    print STDERR $reqOID." MODE_GET\n" if($debug);;
      	    if($reqOID == $myOID+".0"){
  		$request->setValue(ASN_INTEGER, scalar keys (%beancounters));
  	    } elsif($reqOID =~ /$myOID\.([0-9]+)[\.]?([0-9]+)?[\.]?([0-9]+)?[\.]?([0-9]+)?/) {
  
  		my $typeReq=$1;
  		my $vzidReq=$2;
  		my $resReq=$3;
  		my $catReq=$4;
  		my %vz;
  		
  
  		print STDERR "Type:$typeReq, VzID: $vzidReq, Res: $resReq/$resName[$resReq], Cat: $catReq/$catName[$catReq]\n" if($debug);;
  
  		if(!$vzidReq) {
  		    foreach $vzid (sort keys %beancounters) {
  			$vzidReq=$vzid;
  			last;
  		    }
  		}
  		if(!$vzidReq || !exists(${beancounters{$vzidReq}})) {
  		    $request->setError($request_info,SNMP_ERR_NOSUCHNAME);
  		    last;
  		}
  
  		%vz=%{${beancounters{$vzidReq}}};
  
  		if((!defined($resReq) or $resReq == 0) && defined(${vz{0}})) {
  		    $request->setValue(ASN_OCTET_STR, "".${vz{0}});
  		} elsif(!defined($catReq) && defined(${vz{$resReq}[0]})) {
  		    $request->setValue(ASN_INTEGER, ${vz{$resReq}[0]});
  
  		} elsif($catReq< $#catName && defined(${vz{$resReq}[$catReq]})) {
  		    if(9223372036854775807 == ${vz{$resReq}[$catReq+1]}) {
  			$request->setValue(ASN_INTEGER,-1);
  		    } else {
  			$request->setValue(ASN_INTEGER,${vz{$resReq}[$catReq+1]});
  		    }
  		} elsif($resReq<scalar keys %vz && defined(${vz{$resReq+1}[0]})) {
  		    if(9223372036854775807 == ${vz{$resReq}[$catReq+1]}) {
  			$request->setValue(ASN_INTEGER,-1);
  		    } else {
  			$request->setValue(ASN_INTEGER, ${vz{$resReq+1}[0]});
  		    }
  		} else  {
  		    my $finish=1;
  		    foreach $vzid (sort keys %beancounters) {
  			if($vzid > $vzidReq) {
  			    %vz=%{${beancounters{$vzid}}};
  			    $vzidReq=$vzid;
  			    $finish=0;
  			    last;
  			}
  		    }
  		    if(!$finish)  {
  			$request->setValue(ASN_INTEGER, "".${vz{0}});
  		    }
  		}
      		
  
  	    }
  
  	} elsif ($reqMode == MODE_GETNEXT) {
  	    print STDERR $reqOID." MODE_GETNEXT\n" if($debug);
      	    if($reqOID < $myOID+".0"){
      		$request->setOID($OID.".0");
  		$request->setValue(ASN_INTEGER, scalar keys (%beancounters));
  	    } elsif($reqOID =~ /$myOID\.([0-9]+)[\.]?([0-9]+)?[\.]?([0-9]+)?[\.]?([0-9]+)?$/) {
  		my $typeReq=$1;
  		my $vzidReq=$2;
  		my $resReq=$3;
  		my $catReq=$4;
  		my %vz;
  		
  		print STDERR "Type:$typeReq, VzID: $vzidReq, Res: $resReq/$resName[$resReq], Cat: $catReq/$catName[$catReq]\n" if($debug);;
  
  		if(!$vzidReq) {
  		    foreach $vzid (sort keys %beancounters) {
  			$vzidReq=$vzid;
  			last;
  		    }
  		}
  		if(!$vzidReq || !exists(${beancounters{$vzidReq}})) {
  		    $request->setError($request_info,SNMP_ERR_NOSUCHNAME);
  		    last;
  		}
  
  
  		%vz=%{${beancounters{$vzidReq}}};
  
  		if(!defined($resReq) && defined(${vz{0}})) {
      		    $request->setOID($myOID.".1.".$vzidReq.".0");
  		    $request->setValue(ASN_OCTET_STR, "".${vz{0}});
  		} elsif(!defined($catReq) && defined(${vz{$resReq}[0]})) {
      		    $request->setOID($myOID.".1.".$vzidReq.".".$resReq.".0");
  		    $request->setValue(ASN_INTEGER, ${vz{$resReq}[0]});
  		} elsif($catReq< $#catName && defined(${vz{$resReq}[$catReq]})) {
  		    $request->setOID($myOID.".1.".$vzidReq.".".$resReq.".".($catReq+1));
  		    if(9223372036854775807 == ${vz{$resReq}[$catReq+1]}) {
  			$request->setValue(ASN_INTEGER,-1);
  		    } else {
  			$request->setValue(ASN_INTEGER,${vz{$resReq}[$catReq+1]});
  		    }
  		} elsif($resReq<scalar keys %vz && defined(${vz{$resReq+1}[0]})) {
  		    $request->setOID($myOID.".1.".$vzidReq.".".($resReq+1).".0");
  		    if(9223372036854775807 == ${vz{$resReq}[$catReq+1]}) {
  			$request->setValue(ASN_INTEGER,-1);
  		    } else {
  			$request->setValue(ASN_INTEGER, ${vz{$resReq+1}[0]});
  		    }
  		} else  {
  		    my $finish=1;
  		    foreach $vzid (sort keys %beancounters) {
  			if($vzid > $vzidReq) {
  			    %vz=%{${beancounters{$vzid}}};
  			    $vzidReq=$vzid;
  			    $finish=0;
  			    last;
  			}
  		    }
  		    if(!$finish)  {
  			$request->setOID($myOID.".1.".$vzidReq.".0.0");
  			$request->setValue(ASN_OCTET_STR, ${vz{0}});
  		    }
  		}
  	    }
          }
      }
  } 
  
  {
          my $regoid = new NetSNMP::OID($OID); 
          $agent->register($program, $regoid, \&handler);
  }
  
  
  
  #eof // nick
  
=== /etc/snmp/snmpd.conf ===

  rouser my_username priv
  createUser my_username MD5 my_password DES
  perl $OID = '.1.3.6.1.4.1.2021.51'; 
  perl $debugging = '1';
  perl $verbose = '1';
  perl $source = '/proc/user_beancounters'; 
  perl do "/etc/snmp/snmpagent.pl";