17.4.1  No acapi connection .................................................................................. 140 
17.4.2  UDAS search on 8082 phone does not search the OXE users .................... 141 
18.  CALL BACK ............................................................................ 143 
18.1  Glossary ............................................................................................. 143 
18.2  Limits ................................................................................................. 143 
18.3  Configuration ..................................................................................... 143 
18.4  Components ....................................................................................... 143 
18.5  Logs ................................................................................................... 143 
18.6  Use cases ........................................................................................... 144 
18.6.1  “protected callback on busy” or “protected callback on no answer” are not 
working  144 
18.7  Call flow example .............................................................................. 144 
19.  SECURITY CERTIFICATES ........................................................ 147 
19.1  Use cases ........................................................................................... 147 
19.1.1  Certificate import generates an Openssl error .......................................... 147 
19.1.2  No way to access WBM with admin and external authentication ............... 147 
19.1.3  How to install an Intermediate Certificate authority(ies) into the opentouch148 
19.1.4  No way to connect LDAP server ................................................................. 148 
19.1.5  Self signed certificate : VHE curl 60 ........................................................... 148 
19.1.6  VHE reboots at step3 ................................................................................. 149 
20.  MAINTENANCE TOOLS .......................................................... 153 
20.1  Filesystems ......................................................................................... 153 
20.1.1  df - Available disk space ........................................................................... 153 
20.1.2  du - Used disk space ................................................................................. 153 
20.1.3  find - Large files lookup ............................................................................ 154 
20.1.4  lsof - Open file ownership ......................................................................... 154 
20.1.5  mount - Partitions read/write status .......................................................... 154 
20.2  Server hardware performance ............................................................ 155 
20.2.1  Monitoring hard disk changes via hot swap RAID ..................................... 155 
20.2.2  RAID monitoring tools ............................................................................... 155 
20.2.3  hdparm - Disk access speed ...................................................................... 155 
20.3  Server load ........................................................................................ 155 
20.3.1  top - Top processes list .............................................................................. 155 
20.3.2  pstree - Processes hierarchy ...................................................................... 156 
20.3.3  ps - Processes list....................................................................................... 156