Problem
Only a single station can connect to hostapd at a time. Any single station can connect (W8, OSX, iOS, Nexus) but when two or more hosts are connected at the same time the first client loses its connectivity.
However there are no connectivity issues when WPA is not used.
Setup
Linux (Ubuntu server 13.04) wireless router (with separate networks for wired WAN, wired LAN, and Wireless LAN. iptables-save output:
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
-A POSTROUTING -s 10.0.0.0/24 -o p4p1 -j MASQUERADE
-A POSTROUTING -s 10.0.1.0/24 -o p4p1 -j MASQUERADE
COMMIT
*mangle
:PREROUTING ACCEPT [13:916]
:INPUT ACCEPT [9:708]
:FORWARD ACCEPT [4:208]
:OUTPUT ACCEPT [9:3492]
:POSTROUTING ACCEPT [13:3700]
COMMIT
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [9:3492]
-A INPUT -i p4p1 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -i p4p1 -p tcp -m tcp --dport 22 -m state --state NEW -j ACCEPT
-A INPUT -i eth0 -j ACCEPT
-A INPUT -i wlan0 -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A FORWARD -i p4p1 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i eth0 -j ACCEPT
-A FORWARD -i wlan0 -j ACCEPT
-A FORWARD -i lo -j ACCEPT
COMMIT
/etc/hostapd/hostapd.conf
#Wireless Interface
interface=wlan0
driver=nl80211
ssid=<removed>
hw_mode=g
channel=6
max_num_sta=15
auth_algs=3
ieee80211n=1
wmm_enabled=1
wme_enabled=1
#Configure Hardware Capabilities of Interface
ht_capab=[HT40+][SMPS-STATIC][GF][SHORT-GI-20][SHORT-GI-40][RX-STBC12]
#Accept all MAC address
macaddr_acl=0
#Shared Key Authentication
wpa=1
wpa_passphrase=<removed>
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP
rsn_pairwise=CCMP
###IPad Connectivevity Repair
ieee8021x=0
eap_server=0
Wireless Card
#lshw output
product: RT2790 Wireless 802.11n 1T/2R PCIe
vendor: Ralink corp.
physical id: 0
bus info: pci@0000:03:00.0
logical name: mon.wlan0
version: 00
serial: <removed>
width: 32 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list logical wireless ethernet physical
configuration: broadcast=yes driver=rt2800pci driverversion=3.8.0-25-generic firmware=0.34 ip=10.0.1.254 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
#iw list output
Band 1:
Capabilities: 0x272
HT20/HT40
Static SM Power Save
RX Greenfield
RX HT20 SGI
RX HT40 SGI
RX STBC 2-streams
Max AMSDU length: 3839 bytes
No DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 2 usec (0x04)
HT RX MCS rate indexes supported: 0-15, 32
TX unequal modulation not supported
HT TX Max spatial streams: 1
HT TX MCS rate indexes supported may differ
Frequencies:
* 2412 MHz [1] (27.0 dBm)
* 2417 MHz [2] (27.0 dBm)
* 2422 MHz [3] (27.0 dBm)
* 2427 MHz [4] (27.0 dBm)
* 2432 MHz [5] (27.0 dBm)
* 2437 MHz [6] (27.0 dBm)
* 2442 MHz [7] (27.0 dBm)
* 2447 MHz [8] (27.0 dBm)
* 2452 MHz [9] (27.0 dBm)
* 2457 MHz [10] (27.0 dBm)
* 2462 MHz [11] (27.0 dBm)
* 2467 MHz [12] (disabled)
* 2472 MHz [13] (disabled)
* 2484 MHz [14] (disabled)
Bitrates (non-HT):
* 1.0 Mbps
* 2.0 Mbps (short preamble supported)
* 5.5 Mbps (short preamble supported)
* 11.0 Mbps (short preamble supported)
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
max # scan SSIDs: 4
max scan IEs length: 2257 bytes
Coverage class: 0 (up to 0m)
Supported Ciphers:
* WEP40 (00-0f-ac:1)
* WEP104 (00-0f-ac:5)
* TKIP (00-0f-ac:2)
* CCMP (00-0f-ac:4)
Available Antennas: TX 0 RX 0
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* WDS
* monitor
* mesh point
software interface modes (can always be added):
* AP/VLAN
* monitor
valid interface combinations:
* #{ AP } <= 8,
total <= 8, #channels <= 1
Supported commands:
* new_interface
* set_interface
* new_key
* new_beacon
* new_station
* new_mpath
* set_mesh_params
* set_bss
* authenticate
* associate
* deauthenticate
* disassociate
* join_ibss
* join_mesh
* set_tx_bitrate_mask
* set_tx_bitrate_mask
* action
* frame_wait_cancel
* set_wiphy_netns
* set_channel
* set_wds_peer
* Unknown command (84)
* Unknown command (87)
* Unknown command (85)
* Unknown command (89)
* Unknown command (92)
* testmode
* connect
* disconnect
Supported TX frame types:
* IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* mesh point: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* Unknown mode (10): 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
Supported RX frame types:
* IBSS: 0x40 0xb0 0xc0 0xd0
* managed: 0x40 0xd0
* AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* mesh point: 0xb0 0xc0 0xd0
* P2P-client: 0x40 0xd0
* P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* Unknown mode (10): 0x40 0xd0
Device supports RSN-IBSS.
HT Capability overrides:
* MCS: ff ff ff ff ff ff ff ff ff ff
* maximum A-MSDU length
* supported channel width
* short GI for 40 MHz
* max A-MPDU length exponent
* min MPDU start spacing
Device supports TX status socket option.
Device supports HT-IBSS.