Issue with Variable Message Size in Source Script

[bjmarty122]

I attempted to add the uniform random message size option to my script (from the example 0.0 ON 1 UDP DST 127.0.0.1/5000 PERIODIC [1 824:1224]).

Yet, the packets sent are only of the sizeMin (i.e., 824 bytes) and not of a uniform sample from the range minSize to maxSize.

Has anyone else encountered this issue and/or know of a solution?

[weston-nrl]

Are you sure you are using the latest MGEN and you don't maybe have two versions installed? Look at which mgen to be sure? What is your OS?

This works fine for me on Ubuntu:
$ mgen event "on 1 udp dst 127.0.0.1/5000 periodic [1 824:1224]"

$ mgen port 5000
GPSSubscribe(): fopen() error: No such file or directory
GPSSubscribe(): fopen() error: No such file or directory
mgen: version 5.1.1
mgen: starting now ...
15:38:58.640537 START Mgen Version 5.1.1
15:38:58.640671 LISTEN proto>UDP port>5000
15:39:27.057108 RECV proto>UDP flow>1 seq>0 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:27.057009 size>1211 gps>INVALID,999.000000,999.000000,4294966297
15:39:28.057193 RECV proto>UDP flow>1 seq>1 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:28.057052 size>1076 gps>INVALID,999.000000,999.000000,4294966297
15:39:29.057161 RECV proto>UDP flow>1 seq>2 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:29.057037 size>1074 gps>INVALID,999.000000,999.000000,4294966297
15:39:30.057534 RECV proto>UDP flow>1 seq>3 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:30.057412 size>1008 gps>INVALID,999.000000,999.000000,4294966297
15:39:31.057468 RECV proto>UDP flow>1 seq>4 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:31.057396 size>1145 gps>INVALID,999.000000,999.000000,4294966297
15:39:32.057465 RECV proto>UDP flow>1 seq>5 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:32.057393 size>890 gps>INVALID,999.000000,999.000000,4294966297
15:39:33.057528 RECV proto>UDP flow>1 seq>6 src>127.0.0.1/42492 dst>127.0.0.1/5000 sent>15:39:33.057414 size>1213 gps>INVALID,999.000000,999.000000,4294966297
^C15:39:35.530479 STOP

[bjmarty122]

I'm using mgen version 5.02b on the latest Raspberry Pi OS (Linux 5.15.61)

[weston-nrl]

Well, that'd be the problem. 5.02b is 7 years old, and this is a more recent addition.

[bjmarty122]

perfect, thank you!

Odd that the old version is what installed, considering I only installed it a few weeks ago, but I'll go ahead and install the latest, looks to be 5.1.1