To enable t his opt ion, t he init iat or can connect w it h “ Dat a digest ” and “ Header
digest ” .
M a x Con n e ct ion s
The m axim um num ber of iSCSI connect ions.
Er r or Re cov e r y Le v e l
The Er ror Recov er y Lev el ( ERL) is negot iat ed during a leading iSCSI connect ion
login in t radit ional iSCSI ( RFC 3720) and iSER ( RFC 5046) .
ERL= 0 : Se ssion Re cov e r y
ERL= 0 ( Session Recov ery) is t rigger ed w hen failures w it hin a com m and,
w it hin a connect ion, an d/ or w it hin TCP occu r. This causes all of t he previous
connect ions fr om t he failed session t o be r est art ed on a new session by
sending a iSCSI Login Request w it h a zero TSI HRest art all iSCSI connect ions
on any failure.
ERL= 1 : D ige st Fa ilu r e Re cov e r y
ERL= 1 , only applies t o t radit ional iSCSI . For iSCSI / SCTP ( w hich has it s ow n
CRC32C) and bot h t ypes of iSER ( so far) , handling header and dat a ch eck sum
recovery can be disabled.
ERL= 2 : Con n e ct ion Re cov e r y
ERL= 2 , allow s for bot h single and m ult iple com m unicat ion pat h sessions
w it hin a iSCSI Nexus ( and hence t h e SCSI Nex us) t o act ively perform
realligence/ ret ry on iSCSI I TTs from failed iSCSI conn ect ions. ERL= 2 allow s
iSCSI fabrics t o t ak e advant age of recovery in all regards of t ransport level
fabric failures, and in a com plet ely OS independent fashion ( i.e. below t he host
OS st orage st ack) .
High-Availability (N8900, N12000 series/N16000 series only)
HA k eeps y our dat a act ive on t w o separat e syst em s, Thecus Support s
Act ive/ Passive HA — pr ovides a fully redundant inst ance of each node, w hich is only
brought online w hen it s associat ed prim ary n ode fails.
H A se t u p pr oce du r e :
HA needs t w o id e n t ica l Thecu s syst em s ( sam e m odels and sam e hard disk slot
inst alled) w hich ar e capable for high availabilit y feat ur es. One needs t o be set up as
“ Prim ary” and t he second unit as “ Secondar y” , bot h unit s’ needs t o hav e t he RAI D
volum e build up prior inst allat ion.
117
Summary of Contents for N8810U series
Page 61: ...61...
Page 177: ...177...
Page 191: ...Folder to Folder Folder to external device External device to Folder 191...
Page 207: ...Appendix C How to open the top cover N8900 series 207...
Page 208: ...N12000 series N16000 series 208...