Fail to access DVWA which is behind F5 LTM

DVWA replies with a 302 by default. The monitor won't work in this case. If you turn on monitor logging on the pool member, you'll see a message something like this:

[0][13152] 2023-06-23 08:00:06.439883: ID 24 :(_do_ping): time to ping, now=[1687525206.439594][2023-06-23 08:00:06],
status=DOWN [ tmm?=false td=true tr=false addr=::ffff:10.1.20.17:80 mon=/Common/http_dvwa fd=-1 pend=0 #conn=0 up_intvl
=5 dn_intvl=5 timeout=16 time_until_up=0 immed=0 next_ping=[1687525206.438613][2023-06-23 08:00:06] last_ping=[168752520
1.468029][2023-06-23 08:00:01] deadline=[1687525211.141953][2023-06-23 08:00:11] on_service_list=True snd_cnt=10609 rcv_
cnt=0 ]
[0][13152] 2023-06-23 08:00:06.439973: ID 24 :(_send_active_service_ping): pinging [ tmm?=false td=true tr=false addr
=::ffff:10.1.20.17:80 srcaddr=none ]
[0][13152] 2023-06-23 08:00:06.439988: ID 24 :(_connect_to_service): creating new socket (rd0) [ tmm?=false td=true t
r=false addr=::ffff:10.1.20.17:80 ]
[0][13152] 2023-06-23 08:00:06.440059: ID 24 :(_connect_to_service): connect: Operation now in progress [ tmm?=false
td=true tr=false addr=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 ]
[0][13152] 2023-06-23 08:00:06.440082: ID 24 :(_do_ping): post ping, status=DOWN [ tmm?=false td=true tr=false addr=:
:ffff:10.1.20.17:80 mon=/Common/http_dvwa fd=16 pend=1 #conn=1 up_intvl=5 dn_intvl=5 timeout=16 time_until_up=0 immed=0
next_ping=[1687525211.438613][2023-06-23 08:00:11] last_ping=[1687525206.439594][2023-06-23 08:00:06] deadline=[16875252
11.141953][2023-06-23 08:00:11] on_service_list=True snd_cnt=10610 rcv_cnt=0 ]
[0][13152] 2023-06-23 08:00:06.440586: ID 24 :(_main_loop): Activity on pending service, now=[1687525206.440575][2023
-06-23 08:00:06] [ tmm?=false td=true tr=false addr=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 fd=16 pend=1
#conn=1 ]
[0][13152] 2023-06-23 08:00:06.440603: ID 24 :(_send_active_service_ping): pinging [ tmm?=false td=true tr=false addr
=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 ]
[0][13152] 2023-06-23 08:00:06.440620: ID 24 :(_send_active_service_ping): writing [ tmm?=false td=true tr=false addr
=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 ] send=GET /\x0d\x0aHTTP/1.1\x0d\x0aHost: \x0d\x0aConnection: C
lose\x0d\x0a\x0d\x0a

[0][13152] 2023-06-23 08:00:06.440641: ID 24 :(_send_active_service_ping): sent ping [ tmm?=false td=true tr=false ad
dr=::ffff:10.1.20.17:80 mon=/Common/http_dvwa fd=16 pend=0 #conn=0 up_intvl=5 dn_intvl=5 timeout=16 time_until_up=0 imme
d=0 next_ping=[1687525211.438613][2023-06-23 08:00:11] last_ping=[1687525206.439594][2023-06-23 08:00:06] deadline=[1687
525211.141953][2023-06-23 08:00:11] on_service_list=True snd_cnt=10610 rcv_cnt=0 ]
[0][13152] 2023-06-23 08:00:06.442031: ID 24 :(_main_loop): Service ready for read, now=[1687525206.441995][2023-06-2
3 08:00:06] [ tmm?=false td=true tr=false addr=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 fd=16 pend=0 #con
n=0 ]
[0][13152] 2023-06-23 08:00:06.442056: ID 24 :(_recv_active_service_ping): reading [ tmm?=false td=true tr=false addr
=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 ]
[0][13152] 2023-06-23 08:00:06.442089: ID 24 :(_recv_active_service_ping): read failed [ tmm?=false td=true tr=false
addr=::ffff:10.1.20.17:80 srcaddr=::ffff:10.1.20.231%0:46744 ]
[0][13152] 2023-06-23 08:00:06.442130: ID 24 :(shutdown_service) Closing logging file /var/log/monitors/Common_http_d
vwa-Common_10.1.20.17-80.log

Adjust your monitor to look for the redirected URL:
GET /login.php\r\nHTTP/1.1\r\nHost: \r\nConnection: Close\r\n\r\n

https://my.f5.com/manage/s/article/K3224