Hi All,
Here is my experience in implementing iStack between two CE5800 series switch:
Topology:

Things Needed:
- SFP+ Stack Cable
Procedure:
STEP 1: Configure stack parameters on SwitchA(Upper Switch) and SwitchB(Bottom Switch).
@Master Switch set the stack member ID to 1, stack priority to 150, and stack domain ID to 10
<HUAWEI>system-view
Enter system view, return user view with return command.
[~HUAWEI]sysname DATOS
[*HUAWEI]commit
[~DATOS]stack
[~DATOS-stack]stack member 1 priority 150 //The higher priority is the master
[*DATOS-stack]stack member 1 domain 10
[*DATOS-stack]quit
[*DATOS]commit //CE switches requires this command for the configs to take effect
@Slave Switch set the stack member ID to 2, priority 120 and stack domain ID to 10.
<HUAWEI>system-view
Enter system view, return user view with return command.
[~HUAWEI]sysname DATOS1
[*HUAWEI]commit
[~DATOS1]stack
[~DATOS1-stack]stack member 2 priority 120 //The lower priority is the slave
[*DATOS1-stack]stack member 2 domain 10
[*DATOS1-stack]stack member 2 renumber 1 inherit-config //This command will make this switch inherit the configuration of the master switch.
[*DATOS1-stack]q
[*DATOS1]commit
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
STEP 2: Configure Stack Ports
@Master Switch
<DATOS>system-view
[~DATOS]interface stack-port 1/1
[*DATOS-Stack-Port1/1]port member-group interface 10ge 1/0/47 to 1/0/48
[*DATOS-Stack-Port1/1]commit
[~DATOS-Stack-Port1/1]return
@Slave Switch
<DATOS1>System-view
[~DATOS1]interface stack-port 2/1
[*DATOS1-Stack-Port2/1]port member-group interface 10ge 2/0/47 to 2/0/48
[*DATOS1-Stack-Port2/1]commit
[~DATOS1-Stack-Port2/1]return
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
STEP 3: Shutdown both switch
STEP 4: Connect the Stack Cable on the designated ports
STEP 5: Power-on the switch.
Note: Power on the Master switch first then after that, power on the Slave switch.
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
STEP 6: Check the stacking using display commands
<DATOS>dis int br //The ports in switch 2 will merge with switch 1
PHY: Physical
*down: administratively down
^down: standby
(l): loopback
(s): spoofing
(b): BFD down
(e): ETHOAM down
(d): Dampening Suppressed
(p): port alarm down
(dl): DLDP down
(c): CFM down
InUti/OutUti: input utility rate/output utility rate
Interface PHY Protocol InUti OutUti inErrors outErrors
10GE1/0/1 down down 0% 0% 0 0
10GE1/0/2 down down 0% 0% 0 0
10GE1/0/3 down down 0% 0% 0 0
10GE1/0/4 down down 0% 0% 0 0
10GE1/0/5 down down 0% 0% 0 0
10GE1/0/6 down down 0% 0% 0 0
10GE1/0/7 down down 0% 0% 0 0
10GE1/0/8 down down 0% 0% 0 0
10GE1/0/9 down down 0% 0% 0 0
10GE1/0/10 down down 0% 0% 0 0
10GE1/0/11 down down 0% 0% 0 0
10GE1/0/12 down down 0% 0% 0 0
10GE1/0/13 down down 0% 0% 0 0
10GE1/0/14 down down 0% 0% 0 0
10GE1/0/15 down down 0% 0% 0 0
10GE1/0/16 down down 0% 0% 0 0
10GE1/0/17 down down 0% 0% 0 0
10GE1/0/18 down down 0% 0% 0 0
10GE1/0/19 down down 0% 0% 0 0
10GE1/0/20 down down 0% 0% 0 0
10GE1/0/21 down down 0% 0% 0 0
10GE1/0/22 down down 0% 0% 0 0
10GE1/0/23 down down 0% 0% 0 0
10GE1/0/24 down down 0% 0% 0 0
10GE1/0/25 down down 0% 0% 0 0
10GE1/0/26 down down 0% 0% 0 0
10GE1/0/27 down down 0% 0% 0 0
10GE1/0/28 down down 0% 0% 0 0
10GE1/0/29 down down 0% 0% 0 0
10GE1/0/30 down down 0% 0% 0 0
10GE1/0/31 down down 0% 0% 0 0
10GE1/0/32 down down 0% 0% 0 0
10GE1/0/33 down down 0% 0% 0 0
10GE1/0/34 down down 0% 0% 0 0
10GE1/0/35 down down 0% 0% 0 0
10GE1/0/36 down down 0% 0% 0 0
10GE1/0/37 down down 0% 0% 0 0
10GE1/0/38 down down 0% 0% 0 0
10GE1/0/39 down down 0% 0% 0 0
10GE1/0/40 down down 0% 0% 0 0
10GE1/0/41 down down 0% 0% 0 0
10GE1/0/42 down down 0% 0% 0 0
10GE1/0/43 down down 0% 0% 0 0
10GE1/0/44 down down 0% 0% 0 0
10GE1/0/45 down down 0% 0% 0 0
10GE1/0/46 down down 0% 0% 0 0
10GE2/0/1 down down 0% 0% 0 0
10GE2/0/2 down down 0% 0% 0 0
10GE2/0/3 down down 0% 0% 0 0
10GE2/0/4 down down 0% 0% 0 0
10GE2/0/5 down down 0% 0% 0 0
10GE2/0/6 down down 0% 0% 0 0
10GE2/0/7 down down 0% 0% 0 0
10GE2/0/8 down down 0% 0% 0 0
10GE2/0/9 down down 0% 0% 0 0
10GE2/0/10 down down 0% 0% 0 0
10GE2/0/11 down down 0% 0% 0 0
10GE2/0/12 down down 0% 0% 0 0
10GE2/0/13 down down 0% 0% 0 0
10GE2/0/14 down down 0% 0% 0 0
10GE2/0/15 down down 0% 0% 0 0
10GE2/0/16 down down 0% 0% 0 0
10GE2/0/17 down down 0% 0% 0 0
10GE2/0/18 down down 0% 0% 0 0
10GE2/0/19 down down 0% 0% 0 0
10GE2/0/20 down down 0% 0% 0 0
10GE2/0/21 down down 0% 0% 0 0
10GE2/0/22 down down 0% 0% 0 0
10GE2/0/23 down down 0% 0% 0 0
10GE2/0/24 down down 0% 0% 0 0
10GE2/0/25 down down 0% 0% 0 0
10GE2/0/26 down down 0% 0% 0 0
10GE2/0/27 down down 0% 0% 0 0
10GE2/0/28 down down 0% 0% 0 0
10GE2/0/29 down down 0% 0% 0 0
10GE2/0/30 down down 0% 0% 0 0
10GE2/0/31 down down 0% 0% 0 0
10GE2/0/32 down down 0% 0% 0 0
10GE2/0/33 down down 0% 0% 0 0
10GE2/0/34 down down 0% 0% 0 0
10GE2/0/35 down down 0% 0% 0 0
10GE2/0/36 down down 0% 0% 0 0
10GE2/0/37 down down 0% 0% 0 0
10GE2/0/38 down down 0% 0% 0 0
10GE2/0/39 down down 0% 0% 0 0
10GE2/0/40 down down 0% 0% 0 0
10GE2/0/41 down down 0% 0% 0 0
10GE2/0/42 down down 0% 0% 0 0
10GE2/0/43 down down 0% 0% 0 0
10GE2/0/44 down down 0% 0% 0 0
10GE2/0/45 down down 0% 0% 0 0
10GE2/0/46 down down 0% 0% 0 0
40GE1/0/1 down down 0% 0% 0 0
40GE1/0/2 down down 0% 0% 0 0
40GE1/0/3 down down 0% 0% 0 0
40GE1/0/4 down down 0% 0% 0 0
40GE2/0/1 down down 0% 0% 0 0
40GE2/0/2 down down 0% 0% 0 0
40GE2/0/3 down down 0% 0% 0 0
40GE2/0/4 down down 0% 0% 0 0
MEth0/0/0 down down 0% 0% 0 0
NULL0 up up(s) 0% 0% 0 0
Stack-Port1/1 up up 0.01% 0.01% 0 0
10GE1/0/47 up up 0.01% 0.01% 0 0
10GE1/0/48 up up 0.01% 0.02% 0 0
Stack-Port2/1 up up 0.08% 0.01% 0 0
10GE2/0/47 up up 0.01% 0.01% 0 0
10GE2/0/48 up up 0.12% 0.01% 0 0
<DATOS>dis stack top
Stack Topology:
----------------------------------------------
Stack-Port 1 Stack-Port 2
MemberID Status Neighbor Status Neighbor
----------------------------------------------
1 up 2 -- --
2 up 1 -- --
----------------------------------------------
Stack Link:
----------------------------------------------------------------------------
Stack-Port Port Status PeerPort PeerStatus
----------------------------------------------------------------------------
Stack-Port1/1 10GE1/0/47 up 10GE2/0/47 up
Stack-Port1/1 10GE1/0/48 up 10GE2/0/48 up
Stack-Port2/1 10GE2/0/47 up 10GE1/0/47 up
Stack-Port2/1 10GE2/0/48 up 10GE1/0/48 up
----------------------------------------------------------------------------
<DATOS>dis stack
--------------------------------------------------------------------------------
MemberID Role MAC Priority DeviceType Description
--------------------------------------------------------------------------------
1 Master f898-xxxx-xxxx 150 CE6810-48S4Q-LI
2 Standby f898-xxxx-xxxx 120 CE6810-48S4Q-LI
--------------------------------------------------------------------------------
That is all, Thank you for reading!