### Description
When using `ds_select_routes` $du is properly set to the first setid (1) and limiting properly the calls (with maxload), but when the nodes on setid 1 are at maxload and kamailio properly selects the second setid (11) it does NOT set $du.
### Troubleshooting
My dispatcher table is:
``` +-----+-------+-------------------------+-------+----------+-----------------------------------+-------------+ | id | setid | destination | flags | priority | attrs | description | +-----+-------+-------------------------+-------+----------+-----------------------------------+-------------+ | 213 | 1 | sip:1.1.1.1:5080 | 0 | 0 | weight=100;maxload=2;duid=cuore_1 | node1-proxy | | 229 | 1 | sip:2.2.2.2:5080 | 0 | 0 | weight=100;maxload=2;duid=cuore_2 | node2-proxy | | 232 | 11 | sip:3.3.3.3:5080 | 0 | 0 | weight=100;maxload=2;duid=cuore_3 | node3-proxy | +-----+-------+-------------------------+-------+----------+-----------------------------------+-------------+ ```
#### Log Messages
``` [DISPATCH] 1-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: sip:1.1.1.1:5080 [DISPATCH] 2-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: sip:2.2.2.2:5080 [DISPATCH] 3-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: sip:1.1.1.1:5080 [DISPATCH] 4-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: sip:2.2.2.2:5080 [DISPATCH] 5-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: <<null>> [DISPATCH] 6-12743@192.168.1.201: ds_select_routes was succesful (ruri: sip:*TESTCALL@cuore-proxy.sandbox-sngl.com - du: <<null>> ```
### Possible Solutions
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### Additional Information
* **Kamailio Version** - output of `kamailio -v`
``` version: kamailio 5.3.0-dev0 (x86_64/linux) f465d2 flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: f465d2 compiled on 01:08:37 Nov 17 2018 with gcc 4.9.2 ```
* **Operating System**:
<!-- Details about the operating system, the type: Linux (e.g.,: Debian 8.4, Ubuntu 16.04, CentOS 7.1, ...), MacOS, xBSD, Solaris, ...; Kernel details (output of `uname -a`) -->
``` Linux my-proxy 3.16.0-4-amd64 #1 SMP Debian 3.16.39-1 (2016-12-30) x86_64 GNU/Linux ```