Written by J. Moellenkamp
on 
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English   Solaris

Less known Solaris features: Dump device estimates in Solaris 11.2

One reoccuring question from customers is „How large should i size the dump device?“. Since Solaris 11.2 there is a really comfortable way to get a number.
You can use dumpadm to get an estimate of dump device size:

root@solaris:~# dumpadm -e
Estimated space required for dump: 407,81 M

Important to know, the estimate is based on the current dump configuration and the current state of the system. So you should run this comment at a moment that is representative for your usual load. This dependency is obvious when you switch off the dumping of zfs metadata:

root@solaris:~# dumpadm -c kernel-zfs
Dump content      : kernel without ZFS metadata
Dump device       : /dev/zvol/dsk/rpool/dump (dedicated)
Savecore directory: /var/crash
Savecore enabled  : yes
Save compressed   : on
root@solaris:~# dumpadm -e
Estimated space required for dump: 337,02 M
root@solaris:~# dumpadm -c kernel+zfs
Dump content      : kernel with ZFS metadata
Dump device       : /dev/zvol/dsk/rpool/dump (dedicated)
Savecore directory: /var/crash
Savecore enabled  : yes
Save compressed   : on
root@solaris:~# dumpadm -e
Estimated space required for dump: 407,88 M