Varnish

Hello,
From the CWP7 interface I installed Apache & Varnish Cache & Nginx Reverse Proxy but in the dashbord, I visualize a status failled.

If I try to start it I have the following error:
Job for varnish.service failed because the control process is exited with error code. See "systemctl status varnish.service" and "journalctl -xe" for details.

[root@vps44154 ~]# systemctl status varnish.service
● varnish.service - Varnish Cache, a high-performance HTTP accelerator
   Loaded: loaded (/usr/lib/systemd/system/varnish.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since jeu. 2017-12-21 04:42:33 EST; 1min 35s ago
  Process: 17293 ExecStart=/usr/sbin/varnishd -P /var/run/varnish.pid -f $VARNISH_VCL_CONF -a ${VARNISH_LISTEN_ADDRESS}:${VARNISH_LISTEN_PORT} -T ${VARNISH_ADMIN_LISTEN_ADDRESS}:${VARNISH_ADMIN_LISTEN_PORT} -S $VARNISH_SECRET_FILE -s $VARNISH_STORAGE $DAEMON_OPTS (code=exited, status=2)

déc. 21 04:42:33 vps44154 varnishd[17293]: },
déc. 21 04:42:33 vps44154 varnishd[17294]: Child (17304) Panic at: Thu, 21 Dec 2017 09:42:33 GMT
                                            Assert error in MPL_New(), cache/cache_mempool.c line 244:
                                              Condition((pthread_create(&mpl->thread, ((void *)0), mpl_guard, mpl)) == 0) not true....
déc. 21 04:42:33 vps44154 varnishd[17294]: Child (17304) said Child starts
déc. 21 04:42:33 vps44154 varnishd[17293]: Info: Child (17304) said Child starts
déc. 21 04:42:33 vps44154 varnishd[17293]: Debug: Child cleanup complete
déc. 21 04:42:33 vps44154 varnishd[17294]: Child cleanup complete
déc. 21 04:42:33 vps44154 systemd[1]: varnish.service: control process exited, code=exited status=2
déc. 21 04:42:33 vps44154 systemd[1]: Failed to start Varnish Cache, a high-performance HTTP accelerator.
déc. 21 04:42:33 vps44154 systemd[1]: Unit varnish.service entered failed state.
déc. 21 04:42:33 vps44154 systemd[1]: varnish.service failed.
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