Category: OMPROUTE

OSPF on z/OS, basic commands

This article follows on from getting the simplest example of OSPF working. It gives the z/OS commands to display useful information.

I want to

OMP1

I configured multiple TCPIP subsystems, and each one had an OMPROUTE defined. I used a started task OEMP1, as the OMPROUTE for my base TCPIP.

If you have only one TCPIP subsystem, you can use OMPROUTE as your name.

F OMP1,OSPF,areasum

This displays the area summary.

AREA ID        AUTHENTICATION   #IFCS  #NETS  #RTRS  #BRDRS DEMAND     
0.0.0.0           NONE              2      3      3      0  OFF

F OMP1,OSPF,EXTERNAL

EZZ7853I AREA LINK STATE DATABASE                        
TYPE LS DESTINATION     LS ORIGINATOR     SEQNO     AGE   XSUM
                # ADVERTISEMENTS:       0                     
                CHECKSUM TOTAL:         0X0

F OMP1,ospf,list,areas

“Displays all information concerning configured OSPF areas and their associated ranges.”

 EZZ7832I AREA CONFIGURATION 820 
 AREA ID          AUTYPE          STUB? DEFAULT-COST IMPORT-SUMMARIES? 
 0.0.0.0          0=NONE           NO          N/A           N/A 
                                                                               
 --AREA RANGES-- 
 AREA ID          ADDRESS          MASK             ADVERTISE? 
 0.0.0.0          11.11.0.0        255.255.255.0    YES

The entry with address 11.11.0.0 comes from the omproute configuration file entry

range ip_address=11.11.0.1 
      subnet_mask=255.255.255.0 
      ;

F OMP1,ospf,list,ifs

“For each OSPF interface, display the IP address and configured parameters as coded in the
OMPROUTE configuation file” 

 EZZ7833I INTERFACE CONFIGURATION 822 
 IP ADDRESS      AREA             COST RTRNS TRDLY PRI HELLO  DEAD DB_EX 
 10.1.3.2        0.0.0.0             1     5     1   1    10    40    40 
 10.1.1.2        0.0.0.0             1     5     1   1    10    40    40

F OMP1,ospf,list,nbma

“Displays the interface address and polling interval related to interfaces connected to nonbroadcast multiaccess networks.”

 NBMA CONFIGURATION 824 
 INTERFACE ADDR      POLL INTERVAL 
 << NONE CONFIGURED >>

F OMP1,ospf,list,nbrs

“Displays the configured neighbors on non-broadcast networks”

 NEIGHBOR CONFIGURATION 826 
 NEIGHBOR ADDR     INTERFACE ADDRESS   DR ELIGIBLE? 
 << NONE CONFIGURED >>

“Displays all virtual links that have been configured with this router as an endpoint.”

F OMP1,ospf,database,areaid=0.0.0.0 

EZZ7853I AREA LINK STATE DATABASE                           
TYPE LS DESTINATION     LS ORIGINATOR     SEQNO     AGE   XSUM     
  1  1.2.3.4            1.2.3.4         0X80000013   61  0X3D8D    
  1  9.2.3.4            9.2.3.4         0X8000001A  393  0X5A78    
  1 @10.1.1.2           10.1.1.2        0X8000000D  286  0X9E22    
  2  10.1.0.2           1.2.3.4         0X80000006 1241  0XC35E    
  2  10.1.1.1           9.2.3.4         0X80000003  353  0X8197    
  2 @10.1.1.2           10.1.1.2        0X80000005 3600  0X64BD    
  2  10.1.3.1           9.2.3.4         0X80000003  383  0X6BAB    
  2 @10.1.3.2           10.1.1.2        0X80000005 3600  0X4ED1

(LS) Type is described here.

  1. Router links advertisement
  2. Network link advertisement
  3. Summary link advertisement
  4. Summary ASBR advertisement
  5. Autonomous System (AS -think entire network) external link.
  • LS ORIGINATOR: Indicates the router that originated the advertisement.
  • LS DESTINATION: Indicates an IP destination (network, subnet, or host).

From the above

TYPE LS DESTINATION     LS ORIGINATOR
  2  10.1.0.2           1.2.3.4

means router 1.2.3.4 told every one that it has the end of a network link, and its address is 10.1.0.2.

TYPE LS DESTINATION     LS ORIGINATOR      
  1  1.2.3.4            1.2.3.4

says router 1.2.3.4 told every one “here I am, router 1.2.3.4”.

You can use the type and destination in the command:

F OMP1,OSPF,LSA,LSTYPE=…,LSID=…

For example

below.

F OMP1,OSPF,LSA,LSTYPE=1,LSID=1.2.3.4

This allows you to see a lot of information about an individual element of the OSPF database.

LSTYPE=1 is for Router Links Advertisment.

The valid LSID values are given in the output of F OMP1,ospf,database,areaid=0.0.0.0 above.

F OMP1,OSPF,LSA,LSTYPE=1,LSID=9.2.3.4 
EZZ7880I LSA DETAILS  
  LS DESTINATION (ID): 9.2.3.4                     
  LS ORIGINATOR:   9.2.3.4 
  ROUTER TYPE:      (0X00)                         
  # ROUTER IFCS:   3                        
    LINK ID:          10.1.0.2        
    LINK DATA:        10.1.0.3        
    INTERFACE TYPE:   2               
    
    LINK ID:          10.1.1.2        
    LINK DATA:        10.1.1.1        
    INTERFACE TYPE:   2               
   
    LINK ID:          10.1.3.2        
    LINK DATA:        10.1.3.1        
    INTERFACE TYPE:   2
  • LINK ID: Is the IP address of the remote end
  • LINK DATA: Is the IP address of the router’s end
  • INTERFACE TYPE: 2 is “Network links”.

F OMP1,OSPF,LSA,LSTYPE=2,LSID=10.1.0.3

This allows you to see a lot of information about an individual element of the OSPF database.

LSTYPE=2 is “Network links the set of routers attached to a network”.

The valid LSID values are given in the output of F OMP1,ospf,database,areaid=0.0.0.0 above, with type=2.

F OMP1,OSPF,LSA,LSTYPE=2,LSID=10.1.0.3                     
EZZ7880I LSA DETAILS                                   
LS OPTIONS:      E (0X02)                          
LS TYPE:         2                                 
LS DESTINATION (ID): 10.1.0.3                      
LS ORIGINATOR:   9.2.3.4                           
NETWORK MASK:    255.255.255.0                     
 ATTACHED ROUTER: 1.2.3.4          (100)    
 ATTACHED ROUTER: 9.2.3.4          (100)

Where (100) is the metric.

F OMP1,ospf,if 

 EZZ7849I INTERFACES 832 
 IFC ADDRESS     PHYS         ASSOC. AREA     TYPE   STATE  #NBRS  #ADJS 
 10.1.3.2        JFPORTCP4    0.0.0.0         BRDCST   64      1      1 
 10.1.1.2        ETH1         0.0.0.0         BRDCST   64      1      1

F OMP1,ospf,neighbor

EZZ7851I NEIGHBOR SUMMARY 834 
 NEIGHBOR ADDR   NEIGHBOR ID     STATE  LSRXL DBSUM LSREQ HSUP IFC 
 10.1.3.1        9.2.3.4           128      0     0     0  OFF JFPORTCP4 
 10.1.1.1        9.2.3.4           128      0     0     0  OFF ETH1

F OMP1,ospf,routers

EZZ7855I OSPF ROUTERS 836 
DTYPE RTYPE DESTINATION       AREA           COST       NEXT HOP(S) 
  NONE

F OMP1,ospf,statistics

EZZ7856I OSPF STATISTICS 838 
                 OSPF ROUTER ID:         10.1.1.2 (*OSPF) 
                 EXTERNAL COMPARISON:    TYPE 2 
                 AS BOUNDARY CAPABILITY: NO 
                                                                          
 ATTACHED AREAS:                  1  OSPF PACKETS RCVD:             3336 
 OSPF PACKETS RCVD W/ERRS:        0  TRANSIT NODES ALLOCATED:         84 
 TRANSIT NODES FREED:            78  LS ADV. ALLOCATED:                1 
 LS ADV. FREED:                   1  QUEUE HEADERS ALLOC:             32 
 QUEUE HEADERS AVAIL:            32  MAXIMUM LSA SIZE:               512 
 # DIJKSTRA RUNS:                 4  INCREMENTAL SUMM. UPDATES:        0 
 INCREMENTAL VL UPDATES:          0  MULTICAST PKTS SENT:           3371 
 UNICAST PKTS SENT:               7  LS ADV. AGED OUT:                 1 
 LS ADV. FLUSHED:                 1  PTRS TO INVALID LS ADV:           0 
 INCREMENTAL EXT. UPDATES:        0

F OMP1,OSPF,LSA,LSTYPE=2,LSID=10.1.0.3

Where

  • LSTYPE=2 is “Network links the set of routers attached to a network”.
  • 10.1.0.3 is an LS destination (from F OMP1,ospf,database,areaid=…) It comes from the frr definition below
interface eno1
   ip address 10.1.0.3 peer 10.1.0.2/24

Only addresses on the Server are accepted. Addresses from the Laptop are not valid.

In the command F OMP1,OSPF,LSA,LSTYPE=1,LSID=1.2.3.4, some of the LINK IDs seem to be valid.

F OMP1,OSPF,LSA,LSTYPE=1,LSID=x.x.x.x

This allows you to see a lot of information about an individual element of the OSPF database.

The LSATYPE is described in here. LSTYPE=1 is for Router Links Advertisment.

The LSID is one of the routers, for example in

  • F OMP1,ospf,database,areaid=0.0.0.0, it displays, LS DESTINATION LS ORIGINATOR
  • F OMP1,ospf,neighbor, it displays NEIGHBOR ID
F OMP1,OSPF,LSA,LSTYPE=1,LSID=9.2.3.4 
EZZ7880I LSA DETAILS  
  LS DESTINATION (ID): 9.2.3.4                     
  LS ORIGINATOR:   9.2.3.4 
  ROUTER TYPE:      (0X00)                         
  # ROUTER IFCS:   3                               
     LINK ID:          10.1.0.3               
     LINK DATA:        10.1.0.3               
        INTERFACE TYPE:   2
     LINK ID:          10.1.1.1
     LINK DATA:        10.1.1.1              
        INTERFACE TYPE:   2 
     LINK ID:          10.1.3.1              
     LINK DATA:        10.1.3.1              
        INTERFACE TYPE:   2

F OMP1,RTTABLE 

EZZ7847I ROUTING TABLE 842 
 TYPE   DEST NET         MASK      COST    AGE     NEXT HOP(S) 
                                                                        
 STAT*  10.0.0.0         FF000000  0       16079   10.1.1.2 
  SPF   10.1.0.0         FFFFFF00  101     16071   10.1.1.1         (2) 
  SPF*  10.1.1.0         FFFFFF00  1       16078   ETH1 
  SPF*  10.1.3.0         FFFFFF00  1       16078   JFPORTCP4 
  SPF   11.1.0.2         FFFFFFFF  201     4733    10.1.1.1         (2) 
                        0 NETS DELETED, 3 NETS INACTIVE

(2) is the number of equal-cost routes to the destination.

D TCPIP,,OMPROUTE,RTTABLE,DEST=10.1.0.0

gives

EZZ7874I ROUTE EXPANSION 105                   
DESTINATION:    10.1.0.0                       
MASK:           255.255.255.0                  
ROUTE TYPE:     SPF                            
DISTANCE:       101                            
AGE:            943                            
NEXT HOP(S):    10.1.1.1          (ETH1)       
                10.1.3.1          (JFPORTCP4)

Getting OMPROUTE to work on ADCD

While working on getting IP V6 to work, I had problems getting my routing on z/OS working properly. I spent a few days working with TCPIP dynamic routing. What I have written below is what I have learned, it may well be wrong!

The problem…

With TCPIP you can define static routes. For example 

  BEGINRoutes 
  ; Destination        SubnetMask    FirstHop       LinkName    Size 
  ROUTE 9.114.209.0    255.255.255.0    =            ETH2   MTU 1492 
  ROUTE DEFAULT             10.1.1.1                 ETH1   MTU 1492 
  ROUTE DEFAULT6  FE80::8C46:FAFF:FE86:1721    IFPORTCP6  MTU 1492 
  ENDRoutes

This says

  • To send data IP V4 address9.114.209.* go via the link ETH2.
  • Otherwise send all IPV4 traffic to link ETH1 which has address 10.1.1.
  • Send all IP6 traffic to link IFPORTCP6 – which has an IP address of FE80::8C46:FAFF:FE86:1721.

Maintaining lists like these quickly become unmanageable as the size of the network increases.

Dynamically finding the configuration

To solve this problem TCPIP was enhanced to allow the system to discover information. The OMPROUTE daemon manages this.

When OMPROUTE is started, it queries the TCPIP configuration. It merges this information with its configuration data, and sends a request out to participating interfaces “Hello – who are you connected to”. From this information it can build a pictures of the network.

The “Hello – who are you connected to” could produce a lot of output; you can get information about all the links and routers in your environment.

You can divide your network ( from an OMPROUTE perspective ) into areas, and so only routers within an area exchange information. The areas have a number like 1.1.1.1.

The main backbone has number 0.0.0.0 You can send requests between areas. Routers which connect an area to the backbone are called Area Border Routers.

An Area Border Router can be configured as a default route – if a router does not know where to send the packet, send it to the Area Border Router.

Where is this information stored?

It looks like this configuration information is stored in the TCPIP address space, because if you shut down OMPROUTE, the configuration persists. I do not think the information will be updated, until OMPROUTE is restarted.

Routing packets

When a packet needs to be sent to a destination it uses the information provided by OMPROUTE. It uses two algorithms,

  • OSPF -Open shortest path first. As the state of an element in the network changes – the change is broadcast to all the routers. This means a router can quickly respond to a configuration change.
  • RIP – Routing interface protocol. This uses the number of hops. (I would have thought this was the same as the shortest path.) A RIP router has a 30 second heartbeat with its connected networks. If it has not received a response after 180 seconds, it assumes the network link is down.

It looks like OSPF is the better protocol, it is faster to respond to changes, and listens to changes, rather than using a heartbeat, and looks like it scales better.

Creating OMPROUTE

The documentation is not the clearest. I think it assumes you are an expert before you start.

The IBM documentation is here.

My additional steps included

  • The …TCPIP(PROF2) had “520 UDP OROUTED ; RouteD Server”. This name needs to match your started task proc. Either change the TCPIP profile, or use OROUTED as your proc name.
  • OMPROUTE procedure needs a userid with an OMVS segment.
  • Create RACF started task profile. Profile OMPROUTE.* with CLASS(STARTED). STDATA INFORMATION user=…
  • I created USER.Z25A.tcpparms(omp) and copied TCPIP.SEZAINST(EZAORCFG) into it.
  • Initially I forgot to use define the RACF profile CLASS(OPERCMDS) MVS.ROUTEMGR.OMPROUTE

My OMPROUTE procedure was

//OMPROUTE PROC 
//OMPROUTE EXEC PGM=OMPROUTE,REGION=0M,TIME=NOLIMIT, 
// PARM=('ENVAR("_CEE_ENVFILE_S=DD:STDENV")/') 
//* 
//OMPCFG DD DISP=SHR,DSN=USER.Z25A.TCPPARMS(OMP) 
//STDENV DD * 
RESOLVER_CONFIG=//'ADCD.Z25A.TCPPARMS(TCPDATA)' 
OMPROUTE_DEBUG_FILE=/tmp/logs/omproute.debug 
OMPROUTE_IPV6_DEBUG_FILE=/tmp/logs/omprout6.debug 
OMPROUTE_DEBUG_FILE_CONTROL=1000,5 
//SYSPRINT DD SYSOUT=* 
//SYSOUT   DD SYSOUT=* 
//CEEDUMP  DD SYSOUT=*,DCB=(RECFM=FB,LRECL=132,BLKSIZE=132) 
//  PEND

The OMPROUTE configuration is in //OMPCFG … USER.Z25A.TCPPARMS(OMP)

Setting up syslogd

If you are not running SYSLOGD, all of the console messages are prefixed with

BPXF024I (TCPIP) Oct 6 10:11:10 omproute 67174435 : …

When running with SYSLOGD, the default syslogd configuration is to write errors to a file (for example into /var/log/2022/10/06/errors) , and throws away the remainder. I added the following to my syslogd configuration and restarted syslogd.

*.OMPROUTE..* /var/log/%Y/%m/%d/omproute

The messages were then put into the file, and were like

Oct 6 11:52:19 S0W1 omproute[67174443]: EZZ7800I OMPROUTE starting
Oct 6 11:52:24 S0W1 omproute[67174443]: EZZ7817I Using defined OSPF protocol 89
Oct 6 11:52:24 S0W1 omproute[67174443]: EZZ7817I Using defined OSPF protocol 89
Oct 6 11:52:24 S0W1 omproute[67174443]: EZZ7838I Using configuration file: dd:OMPCFG=USER.Z25A.TCPPARMS(OMP)

After OMPROUTE started, In this file I had 19 messages. There were 6 message on the job log.

Configuring OMPROUTE

I had a TCPIP configuration with

INTERFACE IFPORTCP6 
  DEFINE IPAQENET6 
  CHPIDTYPE OSD 
  PORTNAME PORTCP 
  INTFID 7:7:7:7 
  IPADDR FE00::66:7:7:7 

DEVICE PORTB MPCIPA 
 LINK ETH2 IPAQENET PORTB 
HOME 172.26.1.9      ETH2 
                                                 
DEVICE PORTA MPCIPA 
 LINK ETH1 IPAQENET PORTA 
HOME 10.1.1.2        ETH1

In my configuration file I had 

OSPF_INTERFACE 
       Attaches_to_Area =0.0.0.0 
       IP_Address=10.1.1.2 
       Subnet_mask=255.255.255.0 
       NAME=ETH1 
       ; 
RIP_INTERFACE 
       IP_Address=10.1.1.2 
       Subnet_mask=255.255.255.0 
       NAME=PORTA 
       ; 
IPv6_OSPF 
       RouterID = 7.7.7.7
       ; 
IPV6_OSPF_INTERFACE 
       Attaches_to_Area =0.0.0.0 
       NAME=IFPORTCP6 
       ; 
IPv6_RIP_Interface 
       Name = IFPORTCP6
       ;

At startup I got messages in the job log

EZZ7871I NO MATCHING INTERFACE STATEMENTS FOR 172.26.1.20 (EZASAMEMVS)                        
EZZ8171I OMPROUTE IPV4 OSPF IS USING ASSIGNED ROUTER ID 10.1.1.2 FROM ETH1 INTERFACE          
EZZ8171I OMPROUTE IPV6 OSPF IS USING CONFIGURED ROUTER ID 7.7.7.7 FROM IPV6_OSPF STATEMENT

To resolve the problem with EZASAMEMVS I added

 Interface 
      IP_Address=172.26.1.20 
      Name=EZASAMEMVS 
      subnet_mask=255.255.255.0 
      ;

Which basically says this interface is not involved in any dynamic routing.

Once this was resolved the messages in the syslogd file were

EZZ7800I OMPROUTE starting
EZZ7817I Using defined OSPF protocol 89
EZZ7817I Using defined OSPF protocol 89
EZZ7838I Using configuration file: dd:OMPCFG=USER.Z25A.TCPPARMS(OMP)
EZZ7883I Processing interface from stack, address 10.1.1.2, name ETH1, index 5, flags 441
EZZ7883I Processing interface from stack, address 172.26.1.20, name EZASAMEMVS, index 2, flags ffff8c50
EZZ7871I No matching interface statements for 172.26.1.20 (EZASAMEMVS)
EZZ7977I Processing IPv6 interface from stack, address fe00::66:7:7:7, name IFPORTCP6, index 51, flags 1, flags2 0
EZZ7977I Processing IPv6 interface from stack, address fe80::7:7:7:7, name IFPORTCP6, index 51, flags 1, flags2 2
EZZ7882I Processing static route from stack, destination 9.114.209.0, Mask 255.255.255.0, gateway 0.0.0.0 , table EZBMAIN
EZZ7882I Processing static route from stack, destination 0.0.0.0, Mask 0.0.0.0, gateway 10.1.1.1 , table EZBMAIN
EZZ7882I Processing static route from stack, destination ::, prefixlen 0, gateway fe80::8c46:faff:fe86:1721 , table EZBMAIN
EZZ8023I The RIP routing protocol is Enabled
EZZ8036I The IPv6 RIP routing protocol is Enabled
EZZ8171I OMPROUTE IPv4 OSPF is using assigned router ID 10.1.1.2 from ETH1 interface
EZZ7937I The IPv4 OSPF routing protocol is Enabled
EZZ8171I OMPROUTE IPv6 OSPF is using configured router ID 7.7.7.7 from IPV6_OSPF statement
EZZ7937I The IPv6 OSPF routing protocol is Enabled
EZZ7898I OMPROUTE Initialization Complete

Displaying information from OMPROUTE

On the console

You can use commands like

d tcpip,,omp,ospf,list,all
d tcpip,,omp,ipv6ospf,all
d tcpip,,omprtoute,rttable
f omproute,ospf,list,all
f omproute,rttable
f omproute,rt6table
f omproute,IPV6OSPF,if
f omproute,IPV6OSPF,list,all
f omproute,IPV6OSPF,statistics
f omproute,IPV6rip,list,all
f omproute,ospf,nbrs

All of which will list all information about the OSPF configuration.

There are three types of resource you an display

  • OSPF – d tcpip,,omp,ospf,list,all or d tcpip,,omp,IPV6ospf,list,all
  • RIP – d tcpip,,omp,rip,list,all or d tcpip,,omp,IPV6rip,list,all
  • Other interface – d tcpip,,omp,generic,all or d tcpip,,omp,generic6,all

From netstat

Once OMPROUTE was active NETSTAT ROUTE gave me

IPv4 Destinations
Destination        Gateway         Flags    Refcnt     Interface
-----------        -------         -----    ------     ---------
Default            10.1.1.1        UGS      0000000000 ETH1
9.114.209.0/24     0.0.0.0         US       0000000000 ETH1
10.1.1.0/24        0.0.0.0         UO       0000000000 ETH1
10.1.1.2/32        0.0.0.0         UH       0000000000 ETH1
127.0.0.1/32       0.0.0.0         UH       0000000002 LOOPBACK
172.26.1.20/32     0.0.0.0         H        0000000000 EZAZCX
172.26.1.20/32     0.0.0.0         H        0000000000 EZASAMEMVS
IPv6 Destinations
DestIP:   Default
  Gw:     fe80::8c46:faff:fe86:1721
  Intf:   IFPORTCP6         Refcnt:  0000000000
  Flgs:   UGS               MTU:     1492
DestIP:   ::1/128
  Gw:     ::
  Intf:   LOOPBACK6         Refcnt:  0000000000
  Flgs:   UH                MTU:     65535
DestIP:   fe00::66:7:7:7/128
  Gw:     ::
  Intf:   IFPORTCP6         Refcnt:  0000000000
  Flgs:   UH                MTU:     9000
DestIP:   fe80::7:7:7:7/128
  Gw:     ::
  Intf:   IFPORTCP6         Refcnt:  0000000000
  Flgs:   UH                MTU:     9000

Where key fields are

  • Flgs UO. U=The interface is UP, and The route was created by OSPF (includes OSPF external routes).